Commonly used function collation 3 (Random code generation, JSON security filtering)

Randomly generates a string of the specified length, typically used for verification code

function Randomcheckvalid ($len) {
$srcstr = "1A2S3D4F5G6HJ8K9QWERTYUPZXCVBNM";
Mt_srand ();
$strs = "";
for ($i = 0; $i < $len; $i + +) {
$strs. = $srcstr [Mt_rand (0, 30)];
}
return $strs;
}

This function should not be comprehensive enough

function Safejson ($varin)
{
$varout =str_replace ("'", "" ", $varin);
$varout =str_replace ("\ \", "" ", $varout);
$varout =str_replace ("\ n", "", $varout);
$varout =str_replace ("\ R", "", $varout);
return $varout;
}

Commonly used function collation 3 (Random code generation, JSON security filtering)