How to Extract a Substring from a String in PHP

09/06/2021

Contents

In this article, you will learn how to get a substring from a string in PHP.

PHP substr() Function

In PHP, you can extract a substring from a string using the substr() function.

The substr() is a built-in function in PHP that is used to extract a portion of a string.

Syntax

The syntax for the substr() function is as follows:

substr(string $string, int $start [, int $length ]);
Parameters

The substr() function takes three arguments:

  • $string: The string from which you want to extract the substring.
  • $start: The starting position of the substring. If $start is positive, the substring will start from the $start-th character counting from the left. If $start is negative, the substring will start from the $start-th character counting from the right.
  • $length (optional): The length of the substring you want to extract. If $length is not specified, the function will extract the substring from $start to the end of the string. If $length is negative, the function will extract the substring up to that many characters from the end of the string.
Example

Here are some examples of using the substr() function:

<?php
  $string = "Hello, World!";

  // Extract the substring starting from the 7th character and of length 5
  $substring = substr($string, 7, 5);

  // Output: "World"
  echo $substring;

  // Extract the substring starting from the 7th character to the end of the string
  $substring = substr($string, 7);

  // Output: "World!"
  echo $substring;

  // Extract the substring of length 5 counting from the end of the string
  $substring = substr($string, -5, 5);

  // Output: "World"
  echo $substring;
?>
#PHP