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PHP substr() Function

< PHP String Reference

Example

Return "world" from the string:

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

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>";
?>
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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>";
?>
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< PHP String Reference