PHP String Functions Part 1

This post explains with examples some PHP string functions, there are many functions to deal with string, I will explain them all partly.

Here are some of PHP String Functions Examples

str_replace()

Replace all occurrences of the search string with the replacement string.

$string = 'Hello World';
echo str_replace("Hello", "Hi", $string);
// result : Hi World

substr()

Return part of a string

$string = 'Hello World';
echo substr($string, 0, 3);
// result : Hel
echo substr($string, -1);
// result : d
echo substr($string, 0, -1);
// result : Hello Worl

• the first parameter is the string that we want to modify
• the second parameter is the start point of modification (when we use a negative value it will start from the end of string)
• the third parameter is the length of the modified string (when we use a negative value it will ignore a number of characters from the end of string)

trim()

Strip whitespace (or other characters) from the beginning and end of a string

		



$string = '		Hello World ';
echo trim($string);
// result : Hello World

str_split()

Convert a string to an array

$string = 'Hello World';
$array = str_split($string);
print_r($array);
/* will result
Array
(
    [0] 
 => H
    [1] 
 => e
    [2] 
 => l
    [3] 
 => l
    [4] 
 => o
    [5] 
 =>
    [6] 
 => W
    [7] 
 => o
    [8] 
 => r
    [9] 
 => l
    [10] 










 => d
)
*/

/* we can add a second parameter to the function 
which define the length of the letters in each chunk */
$array = str_split($string,3);
print_r($array);
/* will result
Array
(
    [0] 
 => Hel
    [1] 
 => lo
    [2] 
 => Wor
    [3] 

 => ld
)
*/

strlen()

Get string length

$string = 'Hello World';
echo strlen($string);
// result : 11 (counts the whitespace also) 

explode()

Split a string by string

$string = 'Hello World';
$array = explode(' ',$string); // explode the string by whitespace
/* result :
Array
(
    [0] 
 => Hello
    [1] 

 => World
)
*/

implode()

Join array elements with a string

$array = array('Hello','World');
echo implode(' ',$string); // implode the array by whitespace
// result : Hello World