Email user name detection and database

Email user name detection and database tutorial
function Getemailresult (str)
{
$ ("Regemailinfo"). Innerhtml= ' <font color=red> detection, please wait ... </font> ';
var xmlhttp = createxmlhttprequest ();
window.open ("member/regcheck.asp tutorial? rtype=2&/=" +escape (str))
Xmlhttp.open ("Get", "member/regcheck.asp?rtype=2&/=" +escape (str), true);
Xmlhttp.onreadystatechange=function ()
{
if (xmlhttp.readystate==4)
{
if (xmlhttp.status==200)
{
if (xmlhttp.responsetext==0)
{
$ ("Regemailinfo"). Innerhtml= ' verification passed, please continue to complete registration ';
}
else if (xmlhttp.responsetext==1)
{
$ ("Regemailinfo"). Classname= "show null";
$ ("Regemailinfo"). innerhtml= ' Sorry, email address [<b> ' + str + ' </b>] has been registered, a message can only register a username ';
}
Else
{
$ ("Regemailinfo"). Classname= "show null";
$ ("Regemailinfo"). Innerhtml= ' message Format error, please confirm input ';
}
}
}
}
Xmlhttp.send (NULL);
}