PHP 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
|
length | Optional. Specifies the length of the returned string.
Default is to the end of the string.
|
Technical Details
Return Value: | Returns the extracted part of a string, or FALSE on failure, or an empty string |
---|---|
PHP Version: | 4+ |
Changelog: | In PHP Version 5.2.2 to 5.2.6, if the start parameter indicates the position of a negative truncation or beyond, FALSE is returned. Other versions get the string from start |
More Examples
Example 1
Using the start parameter with different positive and negative numbers:
<?php
echo substr("Hello world",10)."<br>";
echo substr("Hello
world",1)."<br>";
echo substr("Hello world",3)."<br>";
echo substr("Hello
world",7)."<br>";
echo substr("Hello world",-1)."<br>";
echo
substr("Hello world",-10)."<br>";
echo substr("Hello world",-8)."<br>";
echo substr("Hello world",-4)."<br>";
?>
Run example »
Example 2
Using the start and length parameters with different positive and negative numbers:
<?php
echo substr("Hello world",0,10)."<br>";
echo substr("Hello
world",1,8)."<br>";
echo substr("Hello world",0,5)."<br>";
echo substr("Hello
world",6,6)."<br>";
echo substr("Hello world",0,-1)."<br>";
echo
substr("Hello world",-10,-2)."<br>";
echo substr("Hello world",0,-6)."<br>";
?>
Run example »
PHP String Reference