PHP function to get the number of occurrences of a string in a file

This article will give you an example of how to get the number of occurrences of a string with substr_count() in PHP, and share it with you for your reference!

substr_count() in PHP can be used to count the number of occurrences of a substring in a specified string.

substr_count()The function is defined as follows:

substr_count(string,substring,start,length)

Parameter description:

string 必需。规定被检查的字符串。 substring 必需。规定要搜索的字符串。 start 可选。规定在字符串中何处开始搜索。 length 可选。规定搜索的长度。

Example:

"; echo substr_count($str,"脚本",16);//指定在第16个字符后开始搜索 echo "
"; echo substr_count($str,"脚本",16,10);//指定从第16个字符开始往后搜索10个字符结束 ?>

Running results;

3 2 1

More examples:

1. Use all parameters

"; // 使用 strlen() 来返回字符串长度 echo substr_count($str,"is")."
"; // 字符串中 "is" 出现的次数 echo substr_count($str,"is",2)."
"; // 字符串缩减为 "is is nice" echo substr_count($str,"is",3)."
"; // 字符串缩减为 "s is nice" echo substr_count($str,"is",3,3)."
"; // 字符串缩减为 "s i" ?>

2. Overlapping substrings

3. If the start and length parameters exceed the string length, output a warning

because of the length The value exceeds the length of the string (3 9 is greater than 12), and a warning will be output.

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