Php judgment character and string inclusion method attribute _ PHP Tutorial

Php determines the inclusion method attributes of characters and strings. The following describes how to use it: 1. strstr: returns a string from the start to the end of the character to be judged. If no return value is returned, the copied code is not included as follows :? Php * is described as follows in the example in the manual:

1. strstr: returns a string from the start to the end of the character to be judged. If no return value exists, it does not contain

The code is as follows:

/* Example in the manual */
$ Email = 'User @ example.com ';
$ Domain = strstr ($ email ,'@');
Echo $ domain; // prints @ example.com

?>

2. stristr: it is used exactly the same as strstr. The only difference is that stristr is case insensitive.

3. strpos: returns a boolean value. FALSE and TRUE. use "=" to judge. the execution speed of strpos is faster than that of the above two functions. In addition, strpos has a parameter that specifies the location for judgment, but is left blank by default. it indicates determining the entire string. the disadvantage is poor support for Chinese characters. usage

The code is as follows:

$ Str = 'abc ';
$ Needle = 'a ';
$ Pos = strpos ($ str, $ needle );

4. use explode for determination

The code is as follows:

Function checkstr ($ str ){
$ Needle = "a"; // determines whether the string contains.
$ Tmparray = explode ($ needle, $ str );
If (count ($ tmparray)> 1 ){
Return true;
} Else {
Return false;
}
}

Substring 1. strstr: returns a string from the start to the end of the character to be judged. If no return value is returned, the code is not included as follows :? Php/* example in the manual...