Data filtering, formatting user input PHP notes

Data filtering, formatting user input PHP notes
1. Filtering
Abstract class filter{
Protected $blackstr = Array ();
Protected $whitestr = Array ();

Abstract function Filtit ($STR);
}
Special symbols for filtering user names
Class Loginfilter extends Filter {
function Filtit ($STR) {
$this->blackstr = Array ("/[\x7f-\xff]/", "/\w/");
Return Preg_replace ($this->blackstr, "", $str);
}
}
Filter the contents of the Input text box
Class Editfilter extends Filter {
function Filtit ($STR) {
$this->blackstr = Array ("/\&/", "/\"/","/\ "/", "/\ /",
"/\\\\/", "/\//", "/-/", "/\*/", "/ /" );
$this->whitestr = Array ("&", "'", "<", ">", "\" ","/","-"," * "," "");
Return Preg_replace ($this->blackstr, $this->whitestr, $STR);
}
}



2.//user's message is a piece of code: for example, JS script, so how to avoid the harm of data in time, the data is displayed correctly

$js = "";//Assume that the user entered a script
$str 1 = base64_encode ($JS);//Encode data using MIME base64
echo $str 1. "
";

$str 2 = Base64_decode ($str 1);//
echo Htmlspecialchars ($JS);//convert special characters to HTML character encoding

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