PHP str_starts_with(): Check If a String starts with a Substring (original) (raw)

Summary: in this tutorial, you’ll learn how to use the PHP str_starts_with() function to check if a string starts with a substring.

Introduction to the PHP str_starts_with() function #

The str_starts_with() function performs a case-senstive search and checks if a string starts with a substring:

str_starts_with ( string <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>h</mi><mi>a</mi><mi>y</mi><mi>s</mi><mi>t</mi><mi>a</mi><mi>c</mi><mi>k</mi><mo separator="true">,</mo><mi>s</mi><mi>t</mi><mi>r</mi><mi>i</mi><mi>n</mi><mi>g</mi></mrow><annotation encoding="application/x-tex">haystack , string </annotation></semantics></math>haystack,stringneedle ) : boolCode language: PHP (php)

The str_starts_with() function has two parameters:

$haystack is the input string to check.
$needle is the substring to search for in the input string.

The str_starts_with() function returns true if the $haystack starts with the $needle or false otherwise.

The str_starts_with() function has been available since PHP 8.0.0. If you use a lower version of PHP, you can polyfill the function like this:

`<?php

if (!function_exists('str_starts_with')) { function str_starts_with($haystack, $needle) { return (string)$needle !== '' && strncmp($haystack, needle,strlen(needle, strlen(needle,strlen(needle)) === 0; } }`Code language: PHP (php)

PHP str_starts_with() function examples #

Let’s take some examples of using the PHP str_starts_with() function.

1) Using PHP str_starts_with() function with single character example #

The following example uses the PHP str_starts_with() function to check if the string 'PHP tutorial' starts with the letter 'P':

`<?php

$str = 'PHP tutorial'; $substr = 'P'; result=strstartswith(result = str_starts_with(result=strstartswith(str, $substr) ? 'is' : 'is not';

echo "The strstr strresult starting with $substr";`Code language: PHP (php)

Output:

The PHP tutorial is starting with PCode language: PHP (php)

2) Using the PHP str_starts_with() function with multiple characters example #

The following example uses the PHP str_starts_with() function to check if the string 'PHP tutorial' starts with the string 'PHP':

`<?php

$str = 'PHP tutorial'; $substr = 'PHP'; result=strstartswith(result = str_starts_with(result=strstartswith(str, $substr) ? 'is' : 'is not';

echo "The strstr strresult starting with $substr";`Code language: PHP (php)

Output:

The PHP tutorial is starting with PHPCode language: PHP (php)

2) Case-sensitive example #

It’s important to keep in mind that the str_starts_with() function performs a case-sensitive search. For example:

`<?php

$str = 'PHP tutorial'; $substr = 'php'; result=strstartswith(result = str_starts_with(result=strstartswith(str, $substr) ? 'is' : 'is not';

echo "The strstr strresult starting with $substr";`Code language: PHP (php)

Output:

The PHP tutorial is not starting with phpCode language: PHP (php)

Summary #

Use the PHP str_starts_with() function to perform a case-sensitive search and check if a string starts with a substring.

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