Usage of trim function in PHP: [trim()] function is a built-in function in PHP. It is used to remove spaces or predefined characters on the left and right sides of a string and return the modified string. Function The syntax is: [trim($string, $charlist)].
The trim() function is a built-in function in PHP that can be used to remove spaces and predefined characters on the left and right sides of a string. The following article will introduce you to the trim() function in PHP and introduce how to use the trim() function. I hope it will be helpful to you.
PHP trim function
trim() function removes whitespace characters or other predefined characters on both sides of a string.
Related functions:
● ltrim() function: removes blank characters or other predefined characters on the left side of the string.
● rtrim() function: Remove blank characters or other predefined characters on the right side of the string.
Basic syntax
trim($string, $charlist)
Parameters: trim() function accepts one required parameter and one optional parameter
$string: Used to specify a string from which whitespace and left and right predefined characters are to be removed; required parameter and cannot be omitted.
$charlist: used to specify the characters to be removed from the string. Optional parameter, which can be omitted; if omitted, all the following characters will be deleted:
●"\0"
- NULL
●"\t ”
- Tag
●“\n”
-New line
●“\x0B”
-Vertical tab character
● “\r”
- Enter
● “”
- Ordinary white space
Return value: It returns a modified string by removing spaces as well as predefined characters on both sides of the left and right string.
Usage example of PHP trim function
Example 1:
<?php $str = "Hello World!"; echo trim($str, "Hell!"); ?>
Output :
o World
Example 2:
<?php header("content-type:text/html;charset=utf-8"); $str = " 欢迎来到php中文网! "; echo trim($str); ?>
Output:
欢迎来到php中文网!
Related video tutorial recommendation: "PHP Tutorial"
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