PHP random string generation code (including upper and lower case letters)_PHP tutorial

The first method: Use string functions to operate

Copy the code The code is as follows:

function createRandomStr($length){
$str = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';//62 characters
$strlen = 62;
while($length > $strlen){
$str .= $str;
$strlen += 62;
}
$str = str_shuffle($str);
return substr($str,0,$length);
}
echo createRandomStr(10);

Second: Using the idea of ​​array and character conversion:

Copy Code The code is as follows:

function createRandomStr($length){
$str = array_merge(range(0,9),range( 'a','z'),range('A','Z'));
shuffle($str);
$str = implode('',array_slice($str,0,$length ));
return $str;
}
echo createRandomStr(10);

After looping 1000 times, the first method is more efficient (first The first calculation is about 0.02 seconds a thousand times, and the second calculation is about 0.06 seconds a thousand times)!

http://www.bkjia.com/PHPjc/327871.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/327871.htmlTechArticleThe first method: Use string function operation to copy the code. The code is as follows: ?php function createRandomStr($length){ $ str = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';/...