CU-BCA-SEM-V-Web Development using Php-Web Technologies-Second Draft

Calling a Function For Each Array Element PHP provides a mechanism, Array_walk( ), for calling a user-defined function once per element in an array: array_walk(array, function_name); The function you define takes in two or, optionally, three arguments: the first is the element's value, the second is the element's key, and the third is a value supplied to array_walk( ) when it is called. For instance, here's another way to print table columns made of the values from an array: Function print_row($value, $key) print(\"$value$keyn\"); $person = array('name' => 'fred', 'age' => 35, 'wife' => 'wilma'); Array_walk($person, 'print_row'); A variant of this situation specifies a historical past colour using the elective 1/3 argument to array_walk( ). This parameter offers us the ability we want to print many tables, with many history colours: Characteristic print_row($value, $key, $colour) print(\"$cost$keyn\"); $person = array('call' => 'fred', 'age' => 35, 'wife' => 'wilma'); Array_walk($man or woman, 'print_row', 'blue'); The array_walk( ) characteristic approaches factors of their inner order. Decreasing an array A cousin of array_walk( ), array_reduce( ), applies a feature to every detail of the array in flip, to construct a single fee: $end result = array_reduce(array, function_name [, default ]); The function takes arguments: the strolling total, and the modern-day price being processed. It needs to go back to the new walking total. As an example, to feature up the squares of the values of an array, use: Characteristic add_up ($running_total, $current_value) $running_total += $current_value * $current_value; go back $running_total; $numbers = array(2, 3, 5, 7); $overall = array_reduce($numbers, 'add_up'); // $overall is now 87 51 CU IDOL SELF LEARNING MATERIAL (SLM)

The array_reduce( ) line makes those characteristic calls: add_up(2,3) add_up(3,5) add_up(38,7) the default argument, if furnished, is a seed value. For example, if we alternate the call to array_reduce( ) inside the preceding example to: $general = array_reduce($numbers, 'add_up', 11); The resulting function calls are: add_up(eleven,2) add_up(13,3) add_up(16,5) add_up(21,7) if the array is empty, Array_reduce( ) returns the default price. If no default cost is given and the array is empty, array_reduce( ) returns null. Looking for values The in_array () function returns true or fake, relying on whether the primary argument is an element within the array given as the second argument: If (in_array(to_find, array [, strict])) ... If the elective third argument is authentic, the forms of to_find and the value in the array should healthy. The default is to now not test the sorts. Here is a simple example: $addresses = array('[email protected]', '[email protected]', '[email protected]'); $got_spam = in_array('junk [email protected]', $addresses); // $got_spam is real $got_milk = in_array('[email protected]', $addresses); // $got_milk is fake personal home page robotically indexes the values in arrays, so in_array( ) is a great deal faster than a loop that tests each cost to discover the only you want. Example Checks whether the consumer has entered information in all of the required fields in a form. Instance looking an array A variation on in_array( ) is the array_search( ) function. At the same time as in_array( ) returns genuine if the cost is located, array_search( ) returns the important thing of the discovered detail: $person = array('call' => 'fred', 'age' => 35, 'wife' => 'wilma'); $okay = array_search($man or woman, 'wilma'); Echo(\"fred's $k is wilman\"); Fred's spouse is wilma 52 CU IDOL SELF LEARNING MATERIAL (SLM)

The array_search( ) function additionally takes the elective 1/3 strict argument, which calls for the varieties of the fee being looked for and the cost inside the array to fit. 3.6SORTING Sorting method arranging statistics in a specific order which may be alphabetical, numerical, growing, or lowering order consistent with some linear courting among records gadgets. It also improves the efficiency of searching. We make a specialty of array kind in PHP. Following suggestions can be protected in this article, • type () • resort () • assort () • resort () • assort () • sort () • Nat sort () • antecessor () • unsort () • unsort () • sort () Let us get started out then, Sort (): Array Sort In PHP Using this method, by default the array is sorted in ascending order. 1 <pre> 2 <?php 3 $var_array = array(10,20,30,40); 4 sort($var_array); 5 print_r($var_array); 6 ?> 7 </pre> Output: Array 53 CU IDOL SELF LEARNING MATERIAL (SLM)

( 54 [0] => 10 [1] => 20 [2] => 30 [3] => 40 ) Moving further let us take a look at this, rsort (): Array Sort In PHP Array is sorted in descending order. 1 <pre> 2 <?php 3 $alphabets = array('a','h','c','f'); 4 rsort($alphabets); 5 foreach ($alphabets as $key => $val) { 6 echo \"$key = $valn\"; 7} 8 ?> 9 </pre> Output: 0=h 1=f 2=c 3=a Third method in this topic is arsort arsort() Associative arrays are sorted in descending order, according to value. <pre> <?php $friends = array(\"a\" => \"Tarun\", \"q\" => \"ashok\", \"b\" => \"charan\", \"l\" => \"sabid\"); arsort($friends); CU IDOL SELF LEARNING MATERIAL (SLM)

foreach ($friends as $key => $val) { echo \"$key = $valn\"; } ?> </pre> Output: l = sabid b = charan q = ashok a = Tarun Let us try and understand how krsort works, krsort():Array Sort In PHP Associative arrays are sorted in descending order, according to the key. <pre> <?php $var_array= array(\"1\"=>\"Ashok\", \"2\"=>\"Tarun\", \"3\"=>\"charan\",\"4\"=>\"sabid\",\"5\"=>\"adarsh\",\"6\"=>\"chintan\",\"7\"=>\"vaibhav\"); krsort($var_array); print_r($var_array); ?> </pre> Output: Array ( [7] => vaibhav [6] => chintan [5] => adarsh [4] => sabid [3] => charan [2] => Tarun 55 CU IDOL SELF LEARNING MATERIAL (SLM)

[1] => Ashok ) Let us move on to the next topic of this article, asort():Array Sort In PHP Associative arrays are sorted in ascending order, according to value. <pre> <?php $var_array= array(\"1\"=>\"Ashok\", \"2\"=>\"Tarun\", \"3\"=>\"charan\",\"4\"=>\"sabid\",\"5\"=>\"adarsh\",\"6\"=>\"chintan\",\"7\"=>\"vaibhav\"); asort($var_array); print_r($var_array); ?> </pre> Output: Array ( [1] => Ashok [2] => Tarun [5] => adarsh [3] => charan [6] => chintan [4] => sabid [7] => vaibhav ) It is time to move to the next topic in this article, ksort() Associative arrays are sorted in ascending order, according to key 1 <pre> 2 <?php 3 $var_array= array(\"7\"=>\"vaibhav\",\"6\"=>\"chintan\",\"1\"=>\"Ashok\",\"5\"=>\"adarsh\", 4 \"2\"=>\"Tarun\", \"3\"=>\"charan\",\"4\"=>\"sabid\"); 56 CU IDOL SELF LEARNING MATERIAL (SLM)

5 ksort($var_array); 6 print_r($var_array); 7 ?> </pre> Output: Array ( [1] => Ashok [2] => Tarun [3] => charan [4] => sabid [5] => adarsh [6] => chintan [7] => vaibhav ) Let us see natsort works, natsort(): Array Sort In PHP Array is sorted by using a “natural order” algorithm. It sorts in such a way that orders alphanumeric strings in the way a human being would maintain key or value associations. 1 <pre> 2 <?php 3 $var_files=array(\"file1.php\",\"file2.php\", \"file3.php\", \"file0.php\"); 4 natsort($var_files); 5 print_r($var_files); 6 ?> 7 </pre> Output: Array ( [3] => file0.php [0] => file1.php [1] => file2.php 57 CU IDOL SELF LEARNING MATERIAL (SLM)

[2] => file3.php ) natcasesort() Array is sorted using a case insensitive “natural order” algorithm. 1 <pre> 2 <?php 3 $var_files = array(\"file12.php\", \"File22.txt\",\"file2.php\", \"file3.php\", \"File1.php\"); 4 natcasesort($var_files); 5 print_r($var_files); 6 ?> 7 </pre> Output: Array ( [4] => File1.php [2] => file2.php [3] => file3.php [0] => file12.php [1] => File22.txt ) Next we are going to take a look at uasort uasort(): Array Sort In PHP Array is sorted using a user-defined comparison function and maintain index association. 1 <pre> 2 <?php 3 function fun($a, $b) 4{ 5 if ($a== $b) return 0; 6 return ($a > $b) ? -1 : 1; 7} 58 CU IDOL SELF LEARNING MATERIAL (SLM)

8 $array = array('a' => -1, 'b' => 6, 'c' => 8, 'd' => -9, 'e' => 1, 'f' => 5, 'g' => 3); 59 9 uasort($array, 'fun'); 10 print_r($array); 11 ?> 12 </pre> Output: Array ( => 8 [b] => 6 [f] => 5 [g] => 3 [e] => 1 [a] => -1 [d] => -9 ) This brings us to the final bit of this Array Sort In PHP article uksort(): Array is sorted by keys using a user-defined comparison function 1 <pre> 2 <?php 3 function fun($a, $b) 4{ 5 if ($a== $b) return 0; 6 return ($a > $b) ? -1 : 1; 7} 8 $array = array('a' => -1, 'b' => 6, 'c' => 8, 'd' => -9, 'e' => 1, 'f' => 5, 'g' => 3); 9 uksort($array, 'fun'); 10 print_r($array); 11 ?> 12 </pre> CU IDOL SELF LEARNING MATERIAL (SLM)

Output: 60 Array ( [g] => 3 [f] => 5 [e] => 1 [d] => -9 => 8 [b] => 6 [a] => -1 ) usort(): Array Sort In PHP Array is sorted by values using a user-defined comparison function. 1 <pre> 2 <?php 3 function fun($a, $b) 4{ 5 if ($a== $b) return 0; 6 return ($a > $b) ? -1 : 1; 7} 8 $array = array('a' => -1, 'b' => 6, 'c' => 8, 'd' => -9, 'e' => 1, 'f' => 5, 'g' => 3); 9 usort($array, 'fun'); 10 print_r($array); 11 ?> 12 </pre> Output: Array ( [0] => 8 [1] => 6 [2] => 5 CU IDOL SELF LEARNING MATERIAL (SLM)

[3] => 3 [4] => 1 [5] => -1 [6] => -9 ) 3.7 SUMMARY  PHP provides you with two types of arrays: indexed and associative. The keys of the indexed array are integers that start at 0. ... The keys of an associative array are strings. And you use associative arrays when you want to access elements by string keys.  Use the sort() function to sort elements of an array in ascending order.  Use the rsort() function to sort elements of an array in descending order.  Use one or more flags to change the sorting behaviour of the sort() or rsort() functions. 3.8 KEYWORDS  Array- An array in PHP is actually an ordered map.  sort() – sorts arrays in ascending order  rsort() – sorts arrays in descending order  asort() – sorts associative arrays in ascending order, according to the value  ksort() – sorts associative arrays in ascending order, according to the key  arsort() – sorts associative arrays in descending order, according to the value  krsort() – sorts associative arrays in descending order, according to the key 3.9 LEARNING ACTIVITY 1. Write a PHP script which will display the colors in the following way: Output: white, green, red,  green  red  white ___________________________________________________________________________ __________________________________________________________________________ 61 CU IDOL SELF LEARNING MATERIAL (SLM)

2. Write a PHP script to calculate and display average temperature, five lowest and highest temperatures. ___________________________________________________________________________ ___________________________________________________________________________ 3.10 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. What is an Array? 2. Explain use of array. 3. What is Associative array? 4. What is sorting? 5. How to traverse an array. Long Questions 1. Explain arrays and advantage of arrays. 2. Explain different types of arrays. 3. Explain different types of functions used for sorting. 4. Difference between indexed, Associative and multi-dimensional arrays. 5. Explain different types of sorting which can be used in arrays. B. Multiple Choice Questions 1. PHP’s numerically indexed array begin with position ___________ a. 1 b. 2 c. 0 d. -1 2. Which of the following are correct ways of creating an array? 62 i) state [0] = \"Karnataka\"; ii) $state [] = array(\"Karnataka\"); iii) $state [0] = \"Karnataka\"; iv) $state = array(\"Karnataka\"); CU IDOL SELF LEARNING MATERIAL (SLM)

a. iii) and iv) b. ii) and iii) c. Only i) d. ii), iii) and iv) 3. What will be the output of the following PHP code? <?php $states = array (\"Karnataka\" => array (\"population\" => \"11,35,000\", \"capital\" => \"Bangalore\"), \"Tamil Nadu\" =>array (“population\" => \"17,90,000\", \"capital\" => \"Chennai\")); echo $states[\"Karnataka”] [\"population\"]; ?> a. Karnataka 11,35,000 b. 11,35,000 c. population 11,35,000 d. Karnataka population 4. Which of the following PHP function will return true if a variable is an array or false if it is not an array? a. this_array() b. is_array() c. do_array() d. in_array() 5. Which in-built function will add a value to the end of an array? 63 a. array_unshift() b. into_array() c. inend_array() CU IDOL SELF LEARNING MATERIAL (SLM)

d. array_push() Answers 1-c, 2-a, 3-b, 4-b, 5-d 3.11 REFERENCES Textbooks  T1: Steven Holzner, WordPress-The Complete Reference, McGraw-Hill.  T2: Robin Nixon, WordPress-MySQL-JavaScript, O’Reilly. Reference Books  R1: Rasmus Lerdorf, Kevin Tatroe, Bob Kaehms, Ric McGrady, WordPress, O’Reilly, Shroff Publishers. 64 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT - 4: FUNCTION STRUCTURE 4.0 Learning Objectives 4.1 Introduction 4.2 User Defining functions 4.3 Passing parameter & return value 4.4 Built-in Functions 4.4.1 Math functions 4.4.2 String functions 4.4.3 Array Functions 4.4.4 Date & time functions 4.4.5 Include 4.4.6 Require 4.5 Summary 4.6 Keywords 4.7 Learning Activity 4.8 Unit End Questions 4.9 References 4.0 LEARNING OBJECTIVES After studying this unit, you will be able to:  Understand functions  Implement functions  Understand build in functions  Work on different type of functions like math functions, string functions etc. 4.1 INTRODUCTION A function is a block of code written in a program to perform some specific project. We will relate capabilities in applications to employees in a place of work in actual lifestyles for better expertise of the manner features paintings. Assume the boss wants his work to calculate the as soon as. So how will this way whole? The worker will take information approximately the statics from the boss, performs calculations and calculate the price variety, 65 CU IDOL SELF LEARNING MATERIAL (SLM)

and suggests the end result to his boss. Capabilities work in a comparable way. They take facts as a parameter, executes a block of statements or carry out operations on those parameters, and return the result. 4.2 USER DEFINING FUNCTIONS User-defined features are the features that may be created through the manner of way of the person at the present time. In easy words, the individual-defined is made through manner of approach of the programmers consistent with their wishes. These are not readymade capabilities like integrated features. In PHP there can be numerous incorporated features and additionally interior you could create your private capabilities for one-of-a-kind capability perform. A function is a block of statements that may be used again and again in a program. A feature will execute while the feature is called (must be referred to as a characteristic). The man or woman defines the characteristic in PHP declared via way of the phrase \"characteristic”. Syntax Function functionname() might be completed; Function – a word to declared the feature. Function name-- a feature name (you may use any name for characteristic). 4.3 PASSING PARAMETER & RETURN VALUE PHP Function Arguments We are able to skip the information in the personal home page feature thru arguments that are separated by commas. The personal home page supports the name by means of price (default), the name by means of reference, default argument values, and variable-duration argument listing. Let's see the example to pass single argument in PHP function. File: functionarg.php 1. <?php 2. function sayHello($name) { 3. echo \"Hello $name<br/>\"; 4. } 66 CU IDOL SELF LEARNING MATERIAL (SLM)

5. sayHello(\"Sonoo\"); 6. sayHello(\"Vimal\"); 7. sayHello(\"John\"); 8. ?> Output: Hello Sonoo Hello Vimal Hello John Let's see the example to pass two argument in PHP function. File: functionarg2.php 1. <?php 2. function sayHello($name,$age){ 3. echo \"Hello $name, you are $age years old<br/>\"; 4. } 5. sayHello(\"Sonoo\",27); 6. sayHello(\"Vimal\",29); 7. sayHello(\"John\",23); 8. ?> Output: Hello Sonoo, you are 27 years old Hello Vimal, you are 29 years old Hello John, you are 23 years old PHP Call By Reference Value passed to the function doesn't modify the actual value by default (call by value). But we can do so by passing value as a reference. By default, value passed to the function is call by value. To pass value as a reference, you need to use ampersand (&) symbol before the argument name. Let's see a simple example of call by reference in PHP. File: functionref.php 1. <?php 67 CU IDOL SELF LEARNING MATERIAL (SLM)

2. function adder(&$str2) 3. { 4. $str2 .= 'Call By Reference'; 5. } 6. $str = 'Hello '; 7. adder($str); 8. echo $str; 9. ?> Output: Hello Call By Reference PHP Function: Default Argument Value We are able to specify a default argument value in function. Whilst calling personal home page feature in case you don't specify any argument; it'll take the default argument. Let's examine a simple instance of the usage of default argument value in PHP function. File: functiondefaultarg.php 1. <?php 2. function sayHello($name=\"Sonoo\"){ 3. echo \"Hello $name<br/>\"; 4. } 5. sayHello(\"Rajesh\"); 6. sayHello();//passing no value 7. sayHello(\"John\"); 8. ?> Output: Hello Rajesh Hello Sonoo Hello John PHP Function: Returning Value 68 CU IDOL SELF LEARNING MATERIAL (SLM)

Let's see an example of PHP function that returns value. File: functiondefaultarg.php 1. <?php 2. function cube($n){ 3. return $n*$n*$n; 4. } 5. echo \"Cube of 3 is: \".cube(3); 6. ?> Output: Cube of 3 is: 27 4.4 BUILT-IN FUNCTIONS PHP Basic Built in Functions have many built-in functions that you can use this function and perform some basic tasks, for example, date (), time (), array () and many more. 4.4.1. PHP Math Functions PHP provides various math functions including; abs ()function: This function is used to get an absolute value of a number. Syntax: number abs (mixed $number) ceil () function: This function is used to get a round up value. Syntax: float ceil (float $value) floor () function: This function is used to get a round down value. Syntax: float floor (float $value) 69 CU IDOL SELF LEARNING MATERIAL (SLM)

sqrt () function: This function is used to get the square root of a number. Syntax: float sqrt (float $arg) decbin() function: This function is used to convert a decimal number into binary. Syntax: string decbin (int $number) dechex () function: This function is used to convert a decimal number into hexadecimal. Syntax: string dechex (int $number) decoct () function: This function is used to convert a decimal number into octal. Syntax: string decoct (int $number) base_convert () function: This function is used to convert a base number to any other base number (hexadecimal number to binary, binary to octal, etc.) Syntax: string base_convert (string $number,int $frombase,int $tobase) bindec() function: This function is used to convert a binary number into decimal. Syntax: number bindec (string $binary_string) 70 CU IDOL SELF LEARNING MATERIAL (SLM)

4.4.2. PHP String Functions PHP provides a number of string functions. Some of the MOST USED string functions are listed below: SYNTAX USES string strtolower ( string It converts a string to lowercase letters $string ) string strtoupper ( string $string It converts a string to uppercase letters ) string ucfirst ( string $str ) It converts the first character of a string to uppercase string lcfirst ( string $str ) It converts the first character of a string to lowercase string ucwords ( string $str ) It converts the first character of each word in a string to uppercase string strrev ( string $string ) It reverses a string int strlen ( string $string ) It returns the length of a string Example: <!DOCTYPE html> <html> <body> <?php $str=\"Hello World\"; $str=strtolower($str); echo \"$str <br>\"; $str=strtoupper($str); 71 CU IDOL SELF LEARNING MATERIAL (SLM)

echo \"$str <br>\"; 72 $str=lcfirst($str); echo \"$str <br>\"; $str=strrev($str); echo \"$str <br>\"; $str=strlen($str); echo \"$str <br>\"; $str=\"hello World\"; $str=ucfirst($str); echo \"$str <br>\"; $str=\"hello world\"; $str=ucwords($str); echo \"$str <br>\"; ?> </body> </html> Output hello world HELLO WORLD hELLO WORLD DLROW OLLEh 11 Hello World Hello World CU IDOL SELF LEARNING MATERIAL (SLM)

4.4.3. Array functions PHP array() function: This function is used to create and return the indexed, associative and multidimensional arrays. Syntax array array ([ mixed $... ] ) Example 1 <!DOCTYPE html> <html> <body> <?php $size = array ( array(\"Pramod\",45,5), array(\"Ben\",65,4), array(\"Santosh\",50,6), ); echo $size[0][0].\": Weight: \".$size[0][1].\", Height: \".$size[0][2].\".<br>\"; ?> </body> 73 </html> Output Pramod: Weight: 45, Height: 5. PHP array_change_key_case() function: This function is used to change the case of the keys of an associative array. Syntax array array_change_key_case ( array $array [, int $case = CASE_LOWER ] ) Example 2 CU IDOL SELF LEARNING MATERIAL (SLM)

<!DOCTYPE html> 74 <html> <body> <?php $weight=array(\"Rahul\"=>\"50\",\"Vibha\"=>\"45\",\"Santa\"=>\"80\"); print_r (array_change_key_case($weight,CASE_UPPER)); ?> </body> </html> Output Array ( [RAHUL] => 50 [VIBHA] => 45 [SANTA] => 80 ) PHP array_chunk() function: This function is used to split array into parts. Syntax array array_chunk ( array $array , int $size [, bool $preserve_keys = false ] ) Example 3 <!DOCTYPE html> <html> <body> <?php $weight=array(\"Rahul\"=>\"50\",\"Vibha\"=>\"45\",\"Santa\"=>\"80\"); print_r(array_chunk($weight,2)); ?> </body> </html Output CU IDOL SELF LEARNING MATERIAL (SLM)

Array ([0] => Array ([0] => 50 [1] =>45) [1] => Array ([0] =>80)) 75 PHP count () function This function is used to count the number of elements in an array. Syntax int count (mixed $array_or_countable [, int $mode = COUNT_NORMAL]) Example 4 <!DOCTYPE html> <html> <body> <?php $flowers=array(\"lily\",\"lotus\",\"rose\",\"Marigold\"); echo count($flowers); ?> </body> </html> Output 4 PHP sort () function This function is used to sort the elements of an array. Syntax bool sort (array&$array [, int $sort_flags = SORT_REGULAR]) Example 5 <!DOCTYPE html> <html> <body> <?php $numbers=array (\"100\",\"160\",\"20\",\"67\"); sort($numbers); CU IDOL SELF LEARNING MATERIAL (SLM)

foreach ($numbers as $n) 76 { echo \"$n<br />\"; } ?> </body> </html> Output 20 67 100 160 PHP array_reverse() function This function is used to reverse the order of the elements of an array. Syntax array array_reverse ( array $array [, bool $preserve_keys = false ] ) Example 6 <!DOCTYPE html> <html> <body> <?php $flowers=array(\"lily\",\"lotus\",\"rose\",\"Marigold\"); $reverseflowers=array_reverse($flowers); foreach( $reverseflowers as $f ) { echo \"$f<br />\"; } ?> CU IDOL SELF LEARNING MATERIAL (SLM)

</body> </html> Output Marigold rose lotus lily PHP array_search() function This function is used to search a value in an array and to return the key of that value in case of a successful search. Syntax mixed array_search ( mixed $needle , array $haystack [, bool $strict = false ] ) Example 7 <!DOCTYPE html> <html> <body> <?php $flowers=array(\"lily\",\"lotus\",\"rose\",\"Marigold\"); $key=array_search(\"rose\",$flowers); echo $key; ?> </body> 77 </html> Output 2 PHP array_intersect() function This function is used to return the matched elements of two array. Syntax CU IDOL SELF LEARNING MATERIAL (SLM)

array array_intersect ( array $array1 , array $array2 [, array $... ] ) Example 8 <!DOCTYPE html> <html> <body> <?php $J_name=array(\"Sohan\",\"Jen\",\"John\",\"Janny\"); $F_name=array(\"Flora\",\"Fatima\",\"Sohan\",\"Flaira\"); $odd_name=array_intersect($J_name,$F_name); foreach( $odd_name as $n ) { echo \"$n<br />\"; } ?> </body> </html> Output Sohan 4.4.4.PHP Date and Time Functions Here is a complete list of date and time functions belonging to the latest PHP 7. These functions are the part of the PHP core so you can use them in your script without any further installation. checkdate() Validates a Gregorian date. date_add() Adds an amount of days, months, years, hours, minutes and seconds to a date. date_create_from_format() Returns a new DateTime object 78 CU IDOL SELF LEARNING MATERIAL (SLM)

formatted according to the specified format. date_create() Returns new DateTime object. date_date_set() Sets a new date. date_default_timezone_get() Returns the default timezone used by all date/time functions in a script. date_default_timezone_set() Sets the default timezone used by all date/time functions in a script. date_diff() Returns the difference between two dates. date_format() Returns a date formatted according to a specified format. date_get_last_errors() Returns the warnings and errors found while parsing a date/time string. date_interval_create_from_date_string() Sets up a DateInterval from the relative parts of the string. date_interval_format() Formats the interval. date_isodate_set() Set a date according to the ISO 8601 standard. date_modify() Modifies the timestamp. date_offset_get() Returns the timezone offset. date_parse_from_format() Returns an associative array with 79 CU IDOL SELF LEARNING MATERIAL (SLM)

date_parse() detailed info about given date date_sub() formatted according to the specified format. date_sun_info() Returns associative array with date_sunrise() detailed info about a specified date. date_sunset() date_time_set() Subtracts an amount of days, date_timestamp_get() months, years, hours, minutes and date_timestamp_set() seconds from a date. date_timezone_get() date_timezone_set() Returns an array with information about sunset/sunrise and twilight begin/end for a specified day and location. Returns time of sunrise for a given day and location. Returns time of sunset for a given day and location. Sets the time. Returns the Unix timestamp representing the date. Sets the date and time based on an Unix timestamp. Return time zone relative to given DateTime. Sets the time zone for the DateTime object. 80 CU IDOL SELF LEARNING MATERIAL (SLM)

date() Formats a local date and time. getdate() Returns date/time information of the gettimeofday() timestamp or the current local gmdate() date/time. gmmktime() gmstrftime() Returns the current time. idate() localtime() Formats a GMT/UTC date and time. microtime() mktime() Get Unix timestamp for a GMT date. strftime() strptime() Formats a GMT/UTC date and time strtotime() according to locale settings. time() Formats a local time/date as integer. Returns the local time. Return the current Unix timestamp with microseconds. Returns the Unix timestamp for a date. Formats a local time/date according to locale settings. Parses a time/date generated with strftime(). Parses an English textual datetime into a Unix timestamp. Returns the current time as a Unix 81 CU IDOL SELF LEARNING MATERIAL (SLM)

timestamp. timezone_abbreviations_list() Returns associative array containing dst, offset and the timezone name. timezone_identifiers_list() Returns an indexed array containing all defined timezone identifiers. timezone_location_get() Returns the location information for a specified timezone. timezone_name_from_abbr() Returns the timezone name from abbreviation. timezone_name_get() Returns the name of the timezone. timezone_offset_get() Returns the timezone offset from GMT. timezone_open() Creates new DateTimeZone object. timezone_transitions_get() Returns all transitions for the timezone. timezone_version_get() Returns the current version of the timezonedb. Date Format The following characters are recognized in the format parameter string format character Description Example returned values Day --- --- D Day of the month, 2 digits with 01 to 31 leading zeros 82 CU IDOL SELF LEARNING MATERIAL (SLM)

The following characters are recognized in the format parameter string format character Description Example returned values D A textual representation of a day, Mon through Sun three letters J Day of the month without leading 1 to 31 zeros l (lowercase 'L') A full textual representation of the Sunday through Saturday day of the week N ISO-8601 numeric representation 1 (for Monday) through 7 (for Sunday) of the day of the week S English ordinal suffix for the day st, nd, rd or th. Works well with j of the month, 2 characters W Numeric representation of the day 0 (for Sunday) through 6 (for Saturday) of the week Z The day of the year (starting from 0 through 365 0) Week --- --- W ISO-8601-week number of years, Example: 42 (the 42nd week in the weeks starting on Monday year) Month --- --- F A full textual representation of a January through December month, such as January or March M Numeric representation of a 01 through 12 month, with leading zeros M A short textual representation of a Jan through Dec month, three letters n Numeric representation of a 1 through 12 83 CU IDOL SELF LEARNING MATERIAL (SLM)

The following characters are recognized in the format parameter string format character Description Example returned values month, without leading zeros T Number of days in the given 28 through 31 month Year --- --- L Whether it's a leap year 1 if it is a leap year, 0 otherwise. O ISO-8601 week-numbering year. Examples: 1999 or 2003 This has the same value as Y, except that if the ISO week number (W) belongs to the previous or next year, that year is used instead. Y A full numeric representation of a Examples: 1999 or 2003 year, 4 digits Y A two-digit representation of a Examples: 99 or 03 year Time --- --- A Lowercase Ante meridiem and am or pm Post meridiem A Uppercase Ante meridiem and AM or PM Post meridiem B Swatch Internet time 000 through 999 G 12-hour format of an hour without 1 through 12 leading zeros G 24-hour format of an hour without 0 through 23 leading zeros 84 CU IDOL SELF LEARNING MATERIAL (SLM)

The following characters are recognized in the format parameter string format character Description Example returned values H 12-hour format of an hour with 01 through 12 leading zeros H 24-hour format of an hour with 00 through 23 leading zeros I Minutes with leading zeros 00 to 59 S Seconds with leading zeros 00 through 59 U Microseconds. Note that date Example: 654321 () will always generate 000000 since it takes an int parameter, whereas DateTime: format () does support microseconds if DateTime was created with microseconds. V Milliseconds. Same note applies as Example: 654 for u. Time zone --- --- E Time zone identifier Examples: UTC, GMT, Atlantic/Azores I (capital i) Whether or not the date is in 1 if Daylight Saving Time, 0 otherwise. daylight saving time O Difference to Greenwich time Example: +0200 (GMT) without colon between hours and minutes P Difference to Greenwich time Example: +02:00 (GMT) with colon between hours and minutes p The same as P, but Example: +02:00 85 CU IDOL SELF LEARNING MATERIAL (SLM)

The following characters are recognized in the format parameter string format character Description Example returned values returns Z instead of +00:00 T Timezone abbreviation Examples: EST, MDT ... Z Timezone offset in seconds. The -43200 through 50400 offset for timezones west of UTC is always negative, and for those easts of UTC is always positive. Full Date/Time --- --- C ISO 8601 date 2004-02-12T15:19:21+00:00 R » RFC 2822 formatted date Example: Thu, 21 Dec 2000 16:01:07 +0200 U Seconds since the Unix Epoch (January 1 1970 00:00:00 GMT) 4.4.5. Theyinclude () function This function is used to copy all the contents of a file called within the function; text wise into a file from which it is called. This happens before the server executes the code. Example: Let’s have a file called even.php with the following code: <?php // file to be included echo \"Hello GeeksforGeeks\" ?> Now let us try to include this file into another php file index.php file. We will see that the contents of both the file are shown. <?php include(\"even.php\"); echo \"<br>Above File is Included\" ?> 86 CU IDOL SELF LEARNING MATERIAL (SLM)

4.4.6.The require() function The require () function performs same as the include () function. It also takes the file that is required and copies the whole code into the file from where theyrequire () function is called. There is a single difference between the include () and require () function which we will see following this example: Let’s have a file called even.php with the following code: <?php // file to be included echo \"Hello GeeksforGeeks\" ?> Now if we try to include this file using require() function this file into a web page we need to use a index.php file. We will see that the contents of both the file are shown. <?php require(\"even.php\"); echo \"<br>Above File is Required\" ?> 4.5 SUMMARY We discussed the types of functions in PHP and also its characteristics. The developers and programmers try to develop the code using these two functions as they don’t have to write it again and also the code are easy to test as it is written based on the type of task it has to perform.  A function is a named block of code that performs a specific task.  Do use functions to create reusable code.  Use the return statement to return a value from a function. 4.6 KEYWORDS  Function- A function is a block of code written in a program to perform a few specific task  abs ()-This function is used to get an absolute value of a number  ceil ()-This function is used to get a round up value  sort ()-This function is used to sort the elements of an array 87 CU IDOL SELF LEARNING MATERIAL (SLM)

 array search()-This function is used to search a value in an array and to return the key of that value in case of a successful search 4.7 LEARNING ACTIVITY 1. Write a function to calculate the factorial of a number (a non-negative integer) ___________________________________________________________________________ ___________________________________________________________________________ 2. Write a function to sort an array ___________________________________________________________________________ ___________________________________________________________________________ 4.8 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. What are functions? 2. Write syntax for defining a function? 3. What is user-defined function? 4. Define use of Date function? 5. Explain parameters? Long Questions 1. Explain all user Defined functions? 2. Explain with example call by value function. 3. Explain with example call by reference function. 4. Explain various PHP string functions? 5. Write a PHP function to generate a random password (contains uppercase, lowercase, numeric and other) using shuffle () function. B. Multiple Choice Questions 1. How many types of functions are available in php? a. 5 b. 4 c. 3 d. 2 2. Which of the following is not a built-in function in php? 88 CU IDOL SELF LEARNING MATERIAL (SLM)

a. print_r() b. fopen() c. fclosed() d. gettype() 3. Why should we use functions? a. Reusability b. Easier error detection c. Easily maintained d. All of these 4. A function name always begins with the keyword _________. a. Fun b. Def c. Function d. None of these 5. A function name cannot start with a ____ a. Alphabet b. Underscore c. Number d. Both C and B Answers 1-d, 2-c, 3-d, 4-c, 5-c 4.9 REFERENCES Textbooks  T1: Steven Holzner, WordPress-The Complete Reference, McGraw-Hill.  T2: Robin Nixon, WordPress-MySQL-JavaScript, O’Reilly. Reference Books  R1: Rasmus Lerdorf, Kevin Tatroe, Bob Kaehms, Ric McGrady, WordPress, O’Reilly, Shroff Publishers. 89 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT - 5:PHP FORMS STRUCTURE 5.0 Learning Objectives 5.1 Introduction 5.2 Form Handling 5.2.1 GET 5.2.2 POST 5.2.3 REQUEST 5.2.4 Form Validation 5.2.5 Form Required 5.2.6 Form URL/Email 5.2.7 Form Complete 5.3 Summary 5.4 Keywords 5.5 Learning Activity 5.6 Unit End Questions 5.7 References 5.0LEARNING OBJECTIVES After studying this unit, you will be able to:  Describe nature of human resource management  Identify scope of human resource  State the need and importance of HRM  List the functions of HRM 5.1 INTRODUCTION One of the most powerful features of PHP is the way it handles HTML forms. The basic concept that is important to understand is that any form element will automatically be available to your PHP scripts. It is a straight HTML form with no special tags of any kind. When the user fills in this form and hits the submit button, the action.php page is called. 90 CU IDOL SELF LEARNING MATERIAL (SLM)

5.2 FORM HANDLING POST Here is the code in PHP, which uses $_POST superglobal to obtain information from the form. basic.php <?php echo \"Thank you for the information <font color=green>\".$_POST[\"name\"]. \"</font>. We will get back to you\"; ?><br> We will call you through this phone number for enquiries: <?php echo $_POST[\"phone\"]; ?> Here is the result that is displayed after opening the HTML file. Output: The HTTP GET method may also be used to produce similar results, as shown below. <?php echo \"Thank you for the information <font color=green>\".$_GET[\"name\"]. \"</font>. We will get back to you\"; ?><br> We will call you through this phone number for enquiries: <?php echo $_POST[\"phone\"]; ?> The above script also produces the same results that have been shown in the previous browser outputs. Therefore, if you wish to use either, the choice of yours. 91 CU IDOL SELF LEARNING MATERIAL (SLM)

An important point to note is that, this form is very basic and is only meant for basic php form example. Form validation is important for live forms to prevent malicious activities such as spamming or hacking. 5.2.1 GET Get request is the default form request. The data passed through get request is visible on the URL browser so it is not secured. It is an associative array of variables passed to the current script via the URL parameters (aka. query string). Note that the array is not only populated for GET requests, but rather for all requests with a query string. You can send limited amount of data through get request. The GET variables are passed through urldecode().In general, a URL with GET data will look like this: http://www.example.com/action.php?name=xyz&age=32 $_GET examples: Assuming the user entered http://example.com/?name=Hannes The above example will output something similar to: Hello Hannes! File: form1.html 1. <form action=\"welcome.php\" method=\"get\"> 2. Name: <input type=\"text\" name=\"name\"/> 3. <input type=\"submit\" value=\"visit\"/> 4. </form> File: welcome.php 1. <?php 2. $name=$_GET[\"name\"];//receiving name field value in $name variable 3. echo \"Welcome, $name\"; 4. ?> When the user fills out the form above and clicks the submit button, the form data is sent for processing to a PHP file named \"welcome.php\". The form data is sent with the HTTP GET method. 5.2.2 POST Post request is widely used to submit form that have large amount of data such as file upload, image upload, login form, registration form etc. The data passed through post 92 CU IDOL SELF LEARNING MATERIAL (SLM)

request is not visible on the URL browser so it is secured. You can send large amount of data through post request. It is an associative array of variables passed to the current script via the HTTP POST method when using application/x-www-form-urlencoded or multipart/form-data as the HTTP Content-Type in the request. $_POST examples: <?php echo 'Hello ' . htmlspecialchars($_POST[\"name\"]) . '!'; ?> Assuming the user POSTed name=Hannes The above example will output something similar to: Hello Hannes! File: form1.html 1. <form action=\"login.php\" method=\"post\"> 2. <table> 3. <tr><td>Name:</td><td><input type=\"text\" name=\"name\"/></td></tr> 4. <tr><td>Password:</td><td><input type=\"password\" name=\"password\"/></td></tr> 5. <tr><td colspan=\"2\"><input type=\"submit\" value=\"login\"/></td></tr> 5. </table> 7. </form> File: login.php 1. <?php 2. $name=$_POST[\"name\"];//receiving name field value in $name variable 3. $password=$_POST[\"password\"];//receiving password field value in $password variable 4. echo \"Welcome: $name, your password is: $password\"; 5. ?> 5.2.3 REQUEST PHP gives another superglobal variable $_REQUEST that contains the estimations of both the $_GET and $_POST factors just as the estimations of the $_COOKIE superglobal variable. When you use this variable, it will return both GET and POST values. <!DOCTYPE html> 93 CU IDOL SELF LEARNING MATERIAL (SLM)

<html lang=\"en\"> <head> <title>Example of PHP $_REQUEST variable</title> </head> <body> <?php if(isset($_REQUEST[\"name\"])){ echo \"<p>Hi, \" . $_REQUEST[\"name\"] . \"</p>\"; } ?> <form method=\"post\" action=\"<?php echo $_SERVER[\"PHP_SELF\"];?>\"> <label for=\"inputName\">Name:</label> <input type=\"text\" name=\"name\" id=\"inputName\"> <input type=\"submit\" value=\"Submit\"> </form> </body> 5.2.4 Form validation Form validation is when we evaluate form fields against specific requirements during processing. We might want to check if a password is longer than 7 characters, or if an email address contains the @ symbol. There is no one-size-fits-all solution to form validation. It depends on the form fields and what we want to evaluate. Simple form validation For our example, we want to evaluate three fields: Username. The username field is required and must be equal to or longer than 3 characters. Email. The email field is required and must be a valid email address. Password. The password field must be longer than 7 characters. <html> <body> 94 CU IDOL SELF LEARNING MATERIAL (SLM)

<form method=\"post\" action=\"<?php echo htmlspecialchars($_SERVER[\"PHP_SELF\"]); ?>\"> Name:* <input type=\"text\" name=\"username\"><br> Email:* <input type=\"email\" name=\"email\"><br> Password:* <input type=\"password\" name=\"password\"><br><br> <input type=\"submit\"> </form> </body> </html> 5.2.5 Form Required  Using PHP forms you can set certain fields to be required and display error messages if they aren't filled in upon submission.  This is essential when making any form for actual use with databases and validation. It is meant to display the error messages we have set up: Example 95 <form method=\"post\" action=\"<?php echo htmlspecialchars($_SERVER[\"PHP_SELF\"]);?>\"> <input type=\"text\" name=\"fullname\" placeholder=\"Full name\"> <span>*<?php echo $fullname_error;?></span><br> <input type=\"text\" name=\"email\" placeholder=\"E-mail\"> <span>*<?php echo $email_error;?></span><br> <input type=\"text\" name=\"website\" placeholder=\"Website URL\"> <span><?php echo $website_error;?></span><br> <textarea name=\"feedback\" rows=\"6\" cols=\"50\" placeholder=\"Feedback\"></textarea><br><br> <input type=\"radio\" name=\"gender\" value=\"f\">F <input type=\"radio\" name=\"gender\" value=\"m\">M <span>*<?php echo $gender_error;?></span><br><br> CU IDOL SELF LEARNING MATERIAL (SLM)

<input type=\"submit\" name=\"submit\" value=\"Submit\"> </form> 5.2.6 Form URL/Email Validate E-mail The easiest and safest way to check whether an email address is well-formed is to use PHP's filter_var() function. In the code below, if the e-mail address is not well-formed, then store an error message: $email = test_input($_POST[\"email\"]); if (!filter_var($email, FILTER_VALIDATE_EMAIL)) { $emailErr = \"Invalid email format\"; } Validate URL The code below shows a way to check if a URL address syntax is valid (this regular expression also allows dashes in the URL). If the URL address syntax is not valid, then store an error message: $website = test_input($_POST[\"website\"]); if (!preg_match(\"/\\b(?:(?:https?|ftp):\\/\\/|www\\.)[-a-z0-9+&@#\\/%?=~_|!:,.;]*[-a-z0- 9+&@#\\/%=~_|]/i\",$website)) { $websiteErr = \"Invalid URL\"; } 5.2.7 Form complete To show the values in the input fields after the user hits the submit button, we add a little PHP script inside the value attribute of the following input fields: name, email, and website. In the comment textarea field, we put the script between the <textarea> and </textarea> tags. The little script outputs the value of the $name, $email, $website, and $comment variables. Then, we also need to show which radio button that was checked. For this, we must manipulate the checked attribute (not the value attribute for radio buttons): Name: <input type=\"text\" name=\"name\" value=\"<?php echo $name;?>\"> E-mail: <input type=\"text\" name=\"email\" value=\"<?php echo $email;?>\"> Website: <input type=\"text\" name=\"website\" value=\"<?php echo $website;?>\"> 96 CU IDOL SELF LEARNING MATERIAL (SLM)

Comment: <textarea name=\"comment\" rows=\"5\" cols=\"40\"><?php echo $comment;?></text area> Gender: <input type=\"radio\" name=\"gender\" <?php if (isset($gender) && $gender==\"female\") echo \"checked\";?> value=\"female\">Female <input type=\"radio\" name=\"gender\" <?php if (isset($gender) && $gender==\"male\") echo \"checked\";?> value=\"male\">Male <input type=\"radio\" name=\"gender\" <?php if (isset($gender) && $gender==\"other\") echo \"checked\";?> value=\"other\">Other PHP - Complete Form Example Here is the complete code for the PHP Form Validation Example: Example 5.3 SUMMARY  Using PHP coding, you can create functional HTML forms with both client-side and server-side functions.  Knowledge in PHP forms lets you ensure your users have a safe experience and the data they input won't be compromised.  If you set certain fields in the forms as required and they are left empty, an error message will be outputted. 97 CU IDOL SELF LEARNING MATERIAL (SLM)

 Required fields ensure you get all the data you need from users during registration (or other process). 5.4 KEYWORDS  Forms- Forms are used to get input from the user and submit it to the web server for processing.  POST-The POST method transfers information via HTTP headers.  GET- PHP $_GET is a PHP super global variable which is used to collect form data after submitting an HTML form with method=\"get\". $_GET can also collect data sent in the URL.  URL- A URL is a Uniform Resource Locator, a tool used to find webpages. A URL is composed of a protocol, a domain name, a path to the webpage, and a webpage name.  Response-super global variable $_REQUEST that contains the estimations of both the $_GET and $_POST factors just as the estimations of the $_COOKIE superglobal variable 5.5 LEARNING ACTIVITY 1. Create two files, one to get the user input, one to respond to the user. ___________________________________________________________________________ ___________________________________________________________________________ 2. Using a poem about the days Monday-Saturday, create a form that will return the relevant line in response to the user's choice of day. ___________________________________________________________________________ ___________________________________________________________________________ 5.6 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. What is Form? 2. Explain use of forms? 3. Explain POST. 4. Explain GET. 5. Explain Response. 98 CU IDOL SELF LEARNING MATERIAL (SLM)

Long Questions 1. Explain the various advantages of Forms? 2. Explain GET through an example. 3. Explain various methods of form validation? 4. How to work with Form URL/Email. Explain with an example? 5. How we can validate form and how to complete it explain? B. Multiple Choice Questions 1. Choose the correct option. a. HTML form elements are used for taking user input. b. HTML form elements are defined inside <for> tag. c. HTML form elements can be of different types. d. All of these. 2. Which one of the following is a form element? a. Text box. b. Radio button. c. Submit button. d. All of these. 3. Which one of the following is incorrect? a. <Label> tag in HTML is used for creating a tag for form elements. b. <label> can be used to increase the clickable area of buttons c. id attribute is used with <label> to increase the clickable area of form elements d. None of these 4. Choose the incorrect option. a. Radio button allows to choose only one option from the given options. b. Default option can be chosen using attribute \"selected\" in radio button c. Default option can be chosen using attribute \"checked\" in radio button. d. Checkbox allows choosing one or more than one options from the given options. 5. Choose the incorrect option. a. action attribute is used inside starting tag of form. b. With the use of action, we can redirect to a page once submit button is clicked. 99 CU IDOL SELF LEARNING MATERIAL (SLM)

c. <form action:\"home.php\"> redirects to the page home.php d. None of these Answers 1-d, 2-d, 3-c, 4-b, 5-c 5.7 REFERENCES Textbooks  T1: Steven Holzner, Wordpress-The Complete Reference, McGraw-Hill.  T2: Robin Nixon, Wordpress-MySQL-JavaScript, O’Reilly. Reference Books  R1: Rasmus Lerdorf, Kevin Tatroe, Bob Kaehms, Ric McGrady, WordPress, O’Reilly, Shroff Publishers. 100 CU IDOL SELF LEARNING MATERIAL (SLM)