w3resource

PHP: substr() function

Description

The substr() function used to cut a part of a string from a string, starting at a specified position.

Version:

(PHP 4 and above)

Syntax:

substr(string_name, start_pos, length_to_cut)

Parameters:

Name Description Required /
Optional		 Type
string_name The input string. Required String
start_pos Refers to the position of the string to start cutting.
A positive number : Start at the specified position in the string.
A negative number : Start at a specified position from the end of the string.		 Required Integer
length_to_cut Length of the string to cut from the main string.
A positive number : Start at the specified position in the string.
A negative number : Start at a specified position from the end of the string.		 Optional Integer

Return value:

Returns the extracted part of string and false when failure.

Value Type: String.

Pictorial Presentation

string_substr

Example - 1: 

<?php
$string1="Welcome to w3resource.com";
echo $string1;
echo '<br>';
echo substr($string1,1);
echo '<br>';
echo substr($string1,1,5);
echo '<br>';
echo substr($string1,0,10);
echo '<br>';
echo substr($string1,-1,1);
echo '<br>';
?>

Output: 

Welcome to w3resource.com
elcome to w3resource.com
elcom
Welcome   to
m

View the example in the browser

Example - 2 : 

<?php
$string1="Welcome to w3resource.com";
echo $string1;
echo '<br>';
echo substr($string1,0,-1);
echo '<br>';
echo substr($string1,3,-3);
echo '<br>';
echo substr($string1,4,-4);
echo '<br>';
echo substr($string1,-3,-2);
echo '<br>';
?>

Output :

Welcome to w3resource.com
Welcome to w3resource.co
come to   w3resource.
ome to w3resource
c

View the example in the browser

Example - 3 :

<?php
$string1="Welcome to w3resource.com";
echo $string1;
echo '<br>';
echo substr($string1,-1);
echo '<br>';
echo substr($string1,-4);
echo '<br>';
echo substr($string1,-5,1);
?>

Output :

Welcome to w3resource.com
m
.com
e

View the example in the browser

See also

PHP Function Reference

Previous: substr_replace
Next: trim



PHP: Tips of the Day

In PHP, there are two versions of logical AND and OR operators.

Operator True if
$a and $b Both $a and $b are true
$a && $b Both $a and $b are true
$a or $b Either $a or $b is true
$a || $b Either $a or $b is true

Note that the && and || opererators have higher precedence than and and or. See table below:

Evaluation Result of $e Evaluated as
$e = false || true True $e = (false || true)
$e = false or true False ($e = false) or true

Because of this it's safer to use && and || instead of and and or.