var browserName = navigator.appName; 
var browserVer = parseInt(navigator.appVersion); 
var ns = (browserName == "Netscape");
var nsMore4 = (ns && browserVer >= 5);
var nsLess4 = (ns && browserVer < 5);
var ie4 = (browserName == "Microsoft Internet Explorer") && navigator.appVersion.indexOf('MSIE 4')>0;
var ie5 = (browserName == "Microsoft Internet Explorer") && navigator.appVersion.indexOf('MSIE 5')>0;
var ie6 = (browserName == "Microsoft Internet Explorer") && navigator.appVersion.indexOf('MSIE 6')>0;
var ie = (browserName == "Microsoft Internet Explorer");
var mac = (navigator.userAgent.indexOf("Mac") != -1);

function getWindowWidth() {
   if (nsLess4){
     return window.innerWidth;
 }else if(nsMore4){
  return document.body.offsetWidth;
 }else{
  return document.body.offsetWidth-20;
 }
 return -1;
}

function checkFields(f_strFormName,f_strAlert,f_strFieldUsername, f_strFieldPAssword) {
	
   var frm = document.forms[f_strFormName]
   if (frm[f_strFieldUsername].value.length < 4 || frm[f_strFieldPAssword].value.length < 4) {
      alert(f_strAlert)
      return false
   }
   else return true
}

function swap_img(img_obj, new_url) {
	img_obj.src = new_url;
	return true;
}

function validateForm(formName, mandatoryFields, errorText)
{
	var errorFields = '';
	var message = errorText + '\n\n';
//	alert(document.forms[formName]['InformationCorrect'].length);

	// loop thru all mandatory fieldnames
	for( i = 0; i <= mandatoryFields.length; i++)
	{
		// get the element from the form
		var elem = document.forms[formName][mandatoryFields[i]];
		if (elem != null)
		{
			// if the element has multiple instances and is not a dropdown
			if (elem.length != null && elem.type != "select-one")
			{
				var blnSelected = false;
				// check each instance
				for(x = 0; x < elem.length; x++)
				{
					if (elem[x].checked)
					{
						// quit if checked
						blnSelected = true;
						break;
					}
				}
				if (!blnSelected)	
					errorFields += ' - ' + elem[0].label + '\n';
			}
			else
			{
				// check if the element is a single checkbox
				if (elem.type == "checkbox")
				{
					if (!elem.checked)
						errorFields += ' - ' + elem.label + '\n';
				}
				else
				{
					if (elem.value.length == 0)
						errorFields += ' - ' + elem.label + '\n';
				}
			}
		}
		
	}
	
	if (errorFields.length > 0)
	{
		alert(message + errorFields);
		return false;
	}
	else
		return true;
}