form not submitted

[mishrask]

function validlogin() {
	userin = document.getElementById("user"); passin = document.getElementById("pass");
	msg = document.getElementById("error");
	user = userin.value; pass = passin.value;
	valid = false; error = ""; k = 0;
	if (user=="" || user==userin.defaultValue) { error = "<p>Your Username please...</p>"; k += 1; }
	if (pass=="" || pass==passin.defaultValue) { error = "<p>Your Password please...</p>"; k += 1; }
	if (k==2) { error = "<p>Your Username and Password please...</p>"; }
	if (k!=0) { showDialog('',error); }
	else {
		obj = ajax();
		obj.onreadystatechange = function() {
			if(obj.readyState==4) {
				error = obj.responseText;
				if(error=="") { valid = true; }
				else { showDialog('',error); }
			}
		}
		obj.open("GET","loginchk.php?name="+user+"&pass="+pass,true);
		obj.send(null);
	}
	return valid;
}

Above function is checking for username & password from a "loginchk.p hp" page. However, if username & password matches with those in the database, then variable "valid" is returned as true. All this is working fine.

However, even if "valid" is true, html page is not submitting the form. Code for html is:

<?php
if ( isset($_POST['btn_login']) ) {
	$username = $_POST['user'];
 	$check = mysql_query("SELECT * FROM users WHERE username = '$username'") or die(mysql_error());
	while ( $info = mysql_fetch_array($check) ) {
		$username = stripslashes($username);
		$pass = md5(stripslashes($_POST['pass']));
		$hour = time() + 7200;
		setcookie(user_id, $info['id'], $hour);
		setcookie(user_name, $username, $hour);
		setcookie(user_key, $pass, $hour);
		header('Location: ./members/');
	} 
} 
else {
?>
	<form action="<?php echo $_SERVER['PHP_SELF']?>" method="post" onsubmit="return validlogin()"><div id="login">
		<input type="text" id="user" maxlength="30" class="text" value="Username" /><br />
		<input type="password" id="pass" maxlength="30" class="text" value="Password" /><br />
		<input type="submit" id="btn_login" class="default" value="Login" onmouseover="hover(this)" onmouseout="out(this)" onmousedown="klick(this)" onmouseup="hover(this)" />
		<div id="error" class="hid"></div>
	</div></form>
<?php
}
?>

[Dormilich]

that’s because of the asynchronous nature of your function. the script doesn’t stop after the send() call (because it’s asynchronous) and therefore valid is still false when you return.

[mishrask]

that’s because of the asynchronous nature of your function. the script doesn’t stop after the send() call (because it’s asynchronous) and therefore valid is still false when you return.

Thanks for the prompt reply.
When I see the value of the variable valid (in firebug console), it is shown as true. Doesn't that mean valid is returned as true by the script? Also, is there any alternative?

[Dormilich]

it shows as true because at the time you look at it, its value has been changed by the callback function.

alternately, use a synchronous AJAX call.