PHP String Functions

substr() Function

Definition and Usage

The substr() function returns a part of a string

Note:

If the start parameter is a negative number and length is less than or equal to start, length becomes 0.

Syntax

substr(string,start,length)

Parameter	Description
string	Required. Specifies the string to return a part of
start	Required. Specifies where to start in the string A positive number - Start at a specified position in the string A negative number - Start at a specified position from the end of the string 0 - Start at the first character in string
length	Optional. Specifies the length of the returned string. Default is to the end of the string. A positive number - The length to be returned from the start parameter Negative number - The length to be returned from the end of the string

Example 1

Return "world" from the string:

<?php
echo substr("Hello world",6);
?>

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Example 2

Using the start parameter with different positive and negative numbers:

<?php
echo substr("Hello world",10)." ";
echo substr("Hello world",1)." ";
echo substr("Hello world",3)." ";
echo substr("Hello world",7)." ";

echo substr("Hello world",-1)." ";
echo substr("Hello world",-10)." ";
echo substr("Hello world",-8)." ";
echo substr("Hello world",-4)." ";
?>

Run Example>>