function returnObjById(id)
{
    if(document.getElementById)
    {
        var returnVar = document.getElementById(id);
    }
    else if (document.all)
    {
        var returnVar = document.all[id];
    }
    else if (document.layers)
    {
    	var returnVar = document.layers[id];
    }
    return returnVar;
}


function Overlay(width, height, text)
{
    var overlay = returnObjById("overlay");
    overlay.style.display = "block";
    overlay.innerHTML = "<p>" + text + "</p>";
}


function GetInput(input)
{
    var inputobj = returnObjById(input);
    return inputobj.value;
}


function GetSelect(input)
{
    var inputobj = document.getElementById(input).value;
    return inputobj;
}


function setFade(op, obj)
{
    var obj2 = document.getElementById(obj);
    var obj = obj2.style;
    if (navigator.userAgent.indexOf("Firefox") != -1)
    {
        if(op >= 100)
        {
            op = 99.999;
        }
    }
    obj.filter = "alpha(opacity=" + op + ")";
    obj.KhtmlOpacity = (op / 100);
    obj.MozOpacity = (op / 100);
    obj.opacity = (op / 100);
}


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("setFade(" + i + ",'" + id + "')",(timer * speed));
            timer++;
        }
    }
    else if(opacStart < opacEnd)
    {
        for(i = opacStart; i <= opacEnd; i++)
        {
            setTimeout("setFade(" + i + ",'" + id + "')",(timer * speed));
            timer++;
	}
    }
} 


function InitAjax()
{
    if(window.XMLHttpRequest)
    {
        xmlhttp = new XMLHttpRequest();
    }
    else
    {
        try
        {
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
	}
        catch(e)
        {
            window.alert("Uw browser ondersteunt geen ajax!");
            return false;
        }
    }
    return xmlhttp;
}

    
function Request(method, page, values, handler)
{
    xmlhttp = InitAjax();
    if(method == "GET")
    {
        xmlhttp.open("GET", page + "?" + values, true);
    }
    else
    {
        xmlhttp.open("POST", page, true);
        xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    }
    xmlhttp.onreadystatechange = function() {
        if(xmlhttp.readyState == 4)
        {
            eval(handler + "('" + xmlhttp.responseText + "')");
        }
    }
    if(method == "GET")
    {
        xmlhttp.send(null);
    }
    else
    {
        xmlhttp.send(values);
    }
}


function fastmessage_handler(Text)
{
    Overlay("300", "50", Text);
    opacity("overlay", 100, 0, 4000);
}


function winkel_handler(Text)
{
    var Result = Text.split("::");
    var lay = returnObjById ( "error_" + Result[0] );
    lay.innerHTML = Result[1];
    ShowDiv( "error_" + Result[0] );
    setTimeout ( "HideDiv( 'error_" + Result[0] + "')", 2000);
}


function ShowDiv(divId)
{
    var Div = returnObjById(divId);
    Div.style.display = "block";
}


function HideDiv(divId)
{
    var Div = returnObjById(divId);
    Div.style.display = "none";
}