- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
function is_base64($s)
{
return (bool) preg_match('/^[a-zA-Z0-9\/\r\n+]*={0,2}$/', $s);
}
var_dump(is_base64("dfdf"));
var_dump(is_base64("CkRldmljZSBOYW1lIC0gTW9kZWw6IDx1bmtub3duPiAtIEhVQVdFSSBIVUFXRUkgWTMwMC0wMTAwCk9wZXJhdGluZyBTeXN0ZW06IEFuZHJvaWQgT1MgNC4xLjEgLyBBUEktMTYgKEh1YXdlaVkzMDAtMDEwMC9DNDc5QjE5Nyk="));