function _showMenu(id_Control)
{
    if(document.getElementById(id_Control).style.display != 'none')
        document.getElementById(id_Control).style.display = 'none';
    else 
    {
        document.getElementById(id_Control).style.display = 'inline';
        document.getElementById(id_Control).innerHTML = MasterPage.sShow(id_Control).value;    
    }
}
function _checkUserRegister()
{
    var txUsername = document.getElementById("txUsername");
    if(txUsername.value == '')
    	document.getElementById("_username").innerHTML = 'Bạn chưa nhập "Tên đăng nhập"';
    else document.getElementById("_username").innerHTML = Dang_ky._checkUserName(txUsername).value; ;
}
function hf_findTextBoxHtml(strObjectName) {	
	
	return document.getElementById(strObjectName);
}
function isEmail(emailStr) {
var emailPat=/^(.+)@(.+)$/
var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
var validChars="\[^\\s" + specialChars + "\]"
var quotedUser="(\"[^\"]*\")"
var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
var atom=validChars + '+'
var word="(" + atom + "|" + quotedUser + ")"
var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")
var matchArray=emailStr.match(emailPat)
if (matchArray==null) {
	//alert("Email address seems incorrect (check @ and .'s)")
	return false
}
var user=matchArray[1]
var domain=matchArray[2]

if (user.match(userPat)==null) {
    //alert("The username doesn't seem to be valid.")
    return false
}

var IPArray=domain.match(ipDomainPat)
if (IPArray!=null) {
    // this is an IP address
	  for (var i=1;i<=4;i++) {
	    if (IPArray[i]>255) {
	        //alert("Destination IP address is invalid!")
		return false
	    }
    }
    return true
    }
}