var isSubmit = false;
function FormSubmit(form){
	if(isSubmit) return false;
	
	isSubmit = true;
	return true;
}

function CharCounter(obj, max){
	if(obj.value.length > max){
		obj.value = obj.value.substring(0, max);
	}
}

function GetScrollTop(){
	if (navigator.appName == "Microsoft Internet Explorer"){
		return document.body.scrollTop;
	} else {
		return window.pageYOffset;
	}	
}

function ReloadCode(img){
	var date = new Date();
	img.src = '/validateCode?t='+date.getTime();
}
	
function SelectAll(o, b){
	if(o){
		if(o.length){
			for(var i=0; i < o.length; i++){
				o[i].checked = b;
			}
		}else{
			o.checked = b;
		}
	}	
}

function SelectAll2(oMain, oChild){
	
	if(oMain.checked) b = true;
	else b = false;

	if(oMain && oChild){
		if(oChild.length){
			for(var i=0; i < oChild.length; i++){
				oChild[i].checked = b;
			}
		}else{
			oChild.checked = b;
		}
	}	
}

function getXmlHttp(){
	var thisXmlHttp;
	if (window.XMLHttpRequest){
		thisXmlHttp=new XMLHttpRequest()
	} else if (window.ActiveXObject) {
		thisXmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
	}
			
	if(thisXmlHttp == null){
		alert ("Browser does not support HTTP Request")
		return
	}	
	return thisXmlHttp;
}

function sendXmlHttp(method, url, send, refresh, zone, hideLoading, enableCallback, loadingStr){
		
	var xDiv = document.getElementById(zone);
	if(xDiv != null){
		var xHttp = getXmlHttp();
		xHttp.onreadystatechange = function(){
			stateChangedWith(xHttp, xDiv, hideLoading, enableCallback, loadingStr);
		}
		
		if(url.indexOf('?')==-1){
			url+= '?aj=y';
		}else{
			url+= '&aj=y';
		}

		xHttp.open(method, url, true)
		if(refresh){
			xHttp.setRequestHeader("If-Modified-Since", "Sat, 1 Jan 2000 00:00:00 GMT");
		}
		if(method == 'POST'){
			xHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
		}
		xHttp.send(send);	
	}
}

function stateChangedWith(xHttp, xDiv, hideLoading, enableCallback, loadingStr) { 
	if(!loadingStr || loadingStr == '') loadingStr = "Loading......";
	
	if(xDiv != null){
		if (xHttp.readyState==4 || xHttp.readyState=="complete"){ 
	
			if(xDiv){
				xDiv.style.display = 'block';
				xDiv.innerHTML = xHttp.responseText;
				if(enableCallback && this.stateChangedCallBack){
					this.stateChangedCallBack();
				}
			}
		} else{
			if(xDiv){
				xDiv.style.display = 'block';
				if(!hideLoading) xDiv.innerHTML = '<div style="text-align: center; vertical-align: middle; margin: 30px;"><br><img src=/images/loading.gif border=0><br>' + loadingStr + '</div>';
				//xDiv.style.display = 'inline';
			}
		}
	}
}

function openMSN(msnId){	
	var winId = msnId.substring(0, msnId.indexOf('@'));	
	window.open('http://settings.messenger.live.com/Conversation/IMMe.aspx?invitee='+msnId+'&mkt=en-hk', 'msnWin'+winId, 'dependent=yes, width=330, height=300, screenX=200, screenY=300, titlebar=no, statusbar=no')
}

/*function opacity(id, opacStart, opacEnd, millisec) { 
    //speed for each frame 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 

    //determine the direction for the blending, if start and end are the same nothing happens 
    if(opacStart > opacEnd) { 
        for(i = opacStart; i >= opacEnd; i--) { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } else if(opacStart < opacEnd) { 
        for(i = opacStart; i <= opacEnd; i++) 
            { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } 
}

//change the opacity for different browsers 
function changeOpac(opacity, id) { 
    var object = document.getElementById(id).style; 
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
}*/