// Global variables
var isCSS, isW3C, isIE4, isNN4, isIE6CSS;
// initialize upon load to let all browsers establish content objects
function initDHTMLAPI( ) {
    if (document.images) {
    	isCSS = (document.body && document.body.style) ? true : false;
        isW3C = (isCSS && document.getElementById) ? true : false;
        isIE4 = (isCSS && document.all) ? true : false;
        isNN4 = (document.layers) ? true : false;
        isIE6CSS = (document.compatMode && document.compatMode.indexOf("CSS1") >= 0) ? true : false;
    }
}
// set event handler to initialize API
window.onload = initDHTMLAPI;
function getObject(obj) {
    var theObj;
    if (typeof obj == "string") {
        if (isW3C) {
            theObj = document.getElementById(obj);
        } else if (isIE4) {
            theObj = document.all(obj);
        } else if (isNN4) {
            theObj = seekLayer(document, obj);
        }
    } else {
        // pass through object reference
        theObj = obj;
    }
    return theObj;
}
function CheckMin(Min, Max)
{
var MinNumber = getObject(Min);
var MaxNumber = getObject(Max);
  if (onlyNumbers(MinNumber.value) && onlyNumbers(MaxNumber.value))
  {
    if (!IsEmpty(MinNumber) && !IsEmpty(MaxNumber))
    {
      if (Math.max(MinNumber.value,MaxNumber.value)==MinNumber.value)
	  {
         alert("Mindestwert kann nicht gr\366\337er sein als der gegebene H\366chstwert " + MaxNumber.value + ". Bitte den Wert \344ndern.");
		 MinNumber.value=""; MinNumber.focus();
	  }
	}
  } 
}
function CheckMax(Min, Max)
{
var MinNumber = getObject(Min);
var MaxNumber = getObject(Max);

  if (onlyNumbers(MaxNumber.value) && onlyNumbers(MinNumber.value))
  {
    if (!IsEmpty(MinNumber) && !IsEmpty(MaxNumber))
    {
      if (Math.min(MinNumber.value,MaxNumber.value)==MaxNumber.value)
	  {
         alert("H\366chstwert kann nicht kleiner sein als der Mindestwert " + MinNumber.value + ". Bitte den Wert \344ndern.");
		 MaxNumber.value=""; MaxNumber.focus(); // hier er maar weer wel op gedaan = focus want error als alleen focus zonder alert
	  }
	}
  } 
}
function IsEmpty(aTextField)
{
  var Empty;
  Empty = ((aTextField.value.length == 0) || (aTextField.value==null)) ?  true : false;
  return Empty;
}

function doNoPref (aTextField)
{
	// voor IE toch de object pakken en aTextField is dus 'id'
	var aTextField = getObject(aTextField); 
  if (!onlyNumbers(aTextField.value) || IsEmpty(aTextField)) {
  	aTextField.value = "no pref"; // aTextField.focus();
  }
}
function EmptyIfPref (aTextField)
{
	// voor IE toch de object pakken en aTextField is dus 'id'
	var aTextField = getObject(aTextField); 
	if (aTextField.value == "no pref") {
		aTextField.value=""; // aTextField.focus();
	}
}
function onlyNumbers(inputString)
{
  var amount_dots = 0;
  var amount_e = 0;
  var answer = true;
  var i;
  for (i=0 ; i < inputString.length ; i++)
  {   
    if ((inputString.charCodeAt(i) < 45) ||
	    (inputString.charCodeAt(i) > 57) ||
		(inputString.charCodeAt(i) ==47))
		{
			if ((inputString.charCodeAt(i) == 69) || (inputString.charCodeAt(i) == 101)) {
			  if (i==0) {
			   answer = false;
			  }
			  else {
			    amount_e = amount_e + 1;
			  }
			}
			else {
			  answer = false;
			}
		}
	if (inputString.charCodeAt(i) == 46)
	   {
	   		amount_dots = amount_dots + 1;
	   }
  }
  if (amount_dots > 1) 
  {
  	answer = false;
  }
  if (amount_e > 1) 
  {
  	answer = false;
  }
 return answer;
} 
function IsLargerThan (ID, getal)
{
	var CompareThis = getObject(ID);
	if (!IsEmpty(CompareThis)) {
		if (parseFloat(CompareThis.value) < parseFloat(getal)) 
		{
			alert("Wert ist kleiner als " + getal + ". Bitte den Wert \344ndern.");
			CompareThis.value=""; CompareThis.focus();
		}
	}
}
function IsSmallerThan (ID, getal)
{
	var CompareThis = getObject(ID);
	
	if (!IsEmpty(CompareThis)) {
		if (parseFloat(getObject(ID).value) > parseFloat(getal)) 
		{
			alert("Wert ist gr\366\337er als " + getal + ". Bitte den Wert \344ndern.");
			CompareThis.value=""; CompareThis.focus();
		}
	}
}
function IsLargerOrEqualTo (ID, getal)
{
	var CompareThis = getObject(ID);
	if (!IsEmpty(CompareThis)) {
		if (parseFloat(CompareThis.value) <= parseFloat(getal)) 
		{
			alert("Wert ist kleiner als oder ebenso gro\337 wie " + getal + ". Bitte den Wert \344ndern.");
			CompareThis.value=""; CompareThis.focus();
		}
	}
}
function IsSmallerOrEqualTo (ID, getal)
{
	var CompareThis = getObject(ID);
	if (!IsEmpty(CompareThis)) {
		if (parseFloat(CompareThis.value) >= parseFloat(getal)) 
		{
			alert("Wert ist gr\366\337er als oder ebenso gro\337 wie " + getal + ". Bitte den Wert \344ndern.");
			CompareThis.value=""; CompareThis.focus();
		}
	}
}
function CheckNumber(ID)
{
	var CheckThis = getObject(ID);
	if (!onlyNumbers (CheckThis.value)) 
	{
		alert("Bitte Nummer eingeben.");
		CheckThis.value=""; CheckThis.focus();
	}
}
function CheckStringLength (ID, maxlength)
{
	var StringObject = getObject(ID);	
	if (!(( StringObject.value==null) || ( StringObject.value.length <= maxlength)))
	{ 
			StringObject.value = StringObject.value.substring(0,maxlength); 
	}
}