php判断一个字符串是不是包含另一个字符串

[墨香年少 32]

function contains($str,$find)
{
    if(strpos($str,$find) !== false){
        return true;
    }
    return false;
}

var_dump(contains("I love china","ove"));
var_dump(contains("this is a pen","this"));
var_dump(contains("今天是个好日子","日子"));
var_dump(contains("今天是个好日子","今天"));

echo "\r\n+++++++++++++++++\r\n\r\n";

var_dump(contains("I love china","water"));
var_dump(contains("今天是个好日子","电脑"));