


How 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
?
3 |
echo strpos("Hello world!","wo"); ?>
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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
1 2 3 4 5 6 |
This script will print:
Not found based (==) test Found based (===) test
The (===) test is correct. |
1
2 3 412 13
14
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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"); } ?> |
1 2 3 4 5 6 | This script will print: Not found based (==) test Found based (===) test The (===) test is correct. |

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