Function and usage of strpos in php

This article mainly introduces the method of using PHP to find the position of a string through strpos. It analyzes the functions and usage techniques of strpos with examples. It has certain reference value. Friends who need it can refer to the examples in this article.

Describes how PHP uses strpos to find the location of a string. The specific analysis is as follows:

strpos is used to find the position where a string first appears in another string. strpos is case-sensitive. If it is not found, it returns false. Therefore, strpos has two types of return values. One is an integer and the other is a bool type. During the development process, you need to pay attention to

<?php
echo strpos("Hello world!","wo");
?>

Output result: 6

Since strpos has two types of return values, it is necessary to determine whether the sub-character is found. When stringing, it is best to use === three equal signs for strict type equality comparison

<?php
$haystack = "needle23423432";
$pos = strpos($haystack, "needle");
if ($pos==false) {
 print("Not found based (==) test\n");
} else {
 print("Found based (==) test\n");
}
if ($pos===false) {
 print("Not found based (===) test\n");
} else {
 print("Found based (===) test\n");
}
?>

The above code returns the following results

This script will print:
 
Not found based (==) test
Found based (===) test
 
The (===) test is correct.

1

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