PHP trim() function: Remove characters from string

In this tutorial, we look at the PHP trim function. We look at how you can remove whitespaces and characters from a string using the trim function in PHP.

This tutorial is a part of our initiative at Flexiple, to write short curated tutorials around often used or interesting concepts.

Table of Contents - PHP Trim:

• What does trim do?
• Code and Explanation
• Closing thoughts

What does the PHP trim() function do?

The trim() function in PHP removes whitespace or any other predefined character from both the left and right sides of a string.

ltrim() and rtrim() are used to remove these whitespaces or other characters from the left and right sides of the string. However, making use of just the trim() function without specifying l or r removes characters from both sides.

Code & Explanation:

In this section, we look at the various syntax, parameters, and return values used in the trim() function. Post that we look at a code snippet using the trim() function.

Syntax:

trim($string, $charlist)

Parameters

• $string - Required. This is the string or the variable containing the string from which you want to remove whitespaces or characters.
• $charlist - Optional. This parameter specifies the character that needs to be removed from the string. If left empty, all the characters mentioned below would be removed.
  • \0 NULL
  • tab
  • 
newline
  • \x0B vertical tab
  • \r carriage return
  • ordinary white space### Return Value:A modified string with whitespaces or the specified characters removed from both sides is returned.

Code using PHP Trim:

<?php// PHP program using trim() $str = "  Hire freelance developer ";// Since a second parameter was not passed// leading and trailing whitespaces are removedecho trim($str);?>

The output for the above code snippet would be as follows:

Hire freelance developer

Now lets look at a case where we pass a second argument.

<?php// removing the predefined character $str = "Hire freelance developer";echo trim($str, "Hir");?>

The output for this code snippet would be the following:

e freelance develope

As you can see the hir from Hire and the r from developer were removed.

Closing thoughts - PHP trim():

There are no caveats as such while using the PHP trim() function. I would recommend practicing the trim() method as it can get tricky at times. Also, try using the ltrim() and rtrim() both these functions have very specific use cases.