How to find a substring in a specified string in php
This article mainly introduces the method of finding substrings in a specified string in PHP. It involves the technique of searching strings with the strpos() function in PHP. It has certain reference value. Friends who need it can refer to it
The example of this article describes the method of finding substrings in a specified string in PHP. The specific analysis is as follows:
The strpos() function can be used to find substrings in PHP. The strpos() function will try to find the first occurrence of a substring in the source string. If found, it returns a non-negative integer indicating the position of the substring. Otherwise it returns a boolean false.
<?php $haystack1 = "2349534134345w3mentor16504381640386488129"; $haystack2 = "w3mentor234953413434516504381640386488129"; $haystack3 = "center234953413434516504381640386488129fyi"; $pos1 = strpos($haystack1, "w3mentor"); $pos2 = strpos($haystack2, "w3mentor"); $pos3 = strpos($haystack3, "w3mentor"); print("pos1 = ($pos1); type is " . gettype($pos1) . "\n"); print("pos2 = ($pos2); type is " . gettype($pos2) . "\n"); print("pos3 = ($pos3); type is " . gettype($pos3) . "\n"); ?>
Output result:
pos1 = (13); type is integer pos2 = (0); type is integer pos3 = (); type is boolean
pos3 returns a bool value, that is, the substring is not found
Summary: The above is the summary of this article All content, I hope it will be helpful to everyone's study.
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