function trim(s) {
	return s.replace(/(^\s*)|(\s*$)/g, "");
}

function checkUserName() { 
	var patrn=/^[a-z]{1}([a-z0-9]|[._]){2,15}$/;   
	if (!patrn.exec(trim($E("UserID").value))){ 
		$E("namemsg").innerHTML = "<font color=red>用户名格式不正确，请重新填写!</font>";
		return false;
	}

	var param;
	param = "/ajax/check_username.asp";
	param += "?uname=" + escape(trim($E("UserID").value));
	//alert(param);
	$E("chkbtn").disabled = true;
	$E("namemsg").innerHTML = "<img src=/images/loading.gif>";
	SendRequest(param, param, "GET", function(responseText) {
		//var f = responseText.substring(0, 1);
		var arr = responseText.split(":");
		//alert(arr.length);
		if(arr.length > 1){
			if (arr[0] == "1") {
				$E("submit").enabled=false; //$E("view").innerHTML = responseText.substring();
			} else {
				$E("submit").enabled=true;
			}
			$E("chkbtn").disabled = false;
			$E("namemsg").innerHTML = arr[1];
		}else{$E("namemsg").innerHTML = "检查失败";}
	});
}
// --------------------------------------------------
function $E(id) {
	return document.getElementById(id);
}

function TryThese() {
	for (i = 0; i < arguments.length; i++) {
		try {
			return arguments[i]();
		} catch (e) {
		}
	}
	return false;
}

function CreateXMLHTTP() {
	return TryThese( function() {
		return new ActiveXObject("Msxml2.XMLHTTP");
	}, function() {
		return new ActiveXObject("Microsoft.XMLHTTP");
	}, function() {
		return new XMLHttpRequest();
	}) || false;
}

function SendRequest(url, param, method, echofun) {
	var xmlHTTP = CreateXMLHTTP();
	if (xmlHTTP) {
		xmlHTTP.onreadystatechange = function() {
			if (xmlHTTP.readyState == 4 && xmlHTTP.status == 200) {
				if (echofun != null) {
					echofun(xmlHTTP.responseText);
				}
			}
		}
		xmlHTTP.open(method, url, true);
		xmlHTTP.setRequestHeader("Content-Length", param.length);
		xmlHTTP.setRequestHeader("CONTENT-TYPE", "application/x-www-form-urlencoded");
		xmlHTTP.send(encodeURI(param));
	} else {
		NoXMLHTTP();
	}
}

function NoXMLHTTP() {
	alert("Sorry, your browser doesn't support XMLHTTP");
}