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HomeBackend DevelopmentPHP TutorialHow to find the occurrence position of a string in php through strpos_PHP tutorial

How to use strpos to find the occurrence position of a string in PHP

This article mainly introduces the method of PHP to find the occurrence position of a string through strpos, and analyzes the function and use of strpos with examples. The skills have certain reference value. Friends who need them can refer to them

The example in this article describes how PHP uses strpos to find the position where a string appears. Share it with everyone for your reference. 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 It is of bool type, you need to pay attention during the development process

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echo strpos("Hello world!","wo");

?>

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echo strpos("Hello world!","wo");

?>

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$haystack = "needle23423432";

$pos = strpos($haystack, "needle");

if ($pos==false) {

print("Not found based (==) testn");

} else {

print("Found based (==) testn");

}

if ($pos===false) {

print("Not found based (===) testn");

} else {

print("Found based (===) testn");

}

?>

Output result: 6

Since strpos has two types of return values, it is best to use === three equal signs to perform a strict type equality comparison when judging whether a substring is found

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This script will print:

 

Not found based (==) test

Found based (===) test

 

The (===) test is correct.

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$haystack = "needle23423432"; $pos = strpos($haystack, "needle"); if ($pos==false) { print("Not found based (==) testn"); } else { print("Found based (==) testn"); } if ($pos===false) { print("Not found based (===) testn"); } else { print("Found based (===) testn"); } ?>
The above code returns the following results ?
1 2 3 4 5 6 This script will print: Not found based (==) test Found based (===) test The (===) test is correct.
I hope this article will be helpful to everyone’s PHP programming design. http://www.bkjia.com/PHPjc/969353.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/969353.htmlTechArticlephp method to find the occurrence position of a string through strpos This article mainly introduces php to find the occurrence position of a string through strpos Methods and examples analyze the functions and usage techniques of strpos, with...
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