function toggleClass(tabName, intActive)
{
	if(!intActive)
	{
		if(document.getElementById(tabName).className == 'tab_' + tabName + '_active')
			document.getElementById(tabName).className = 'tab_' + tabName + '_inactive';
		else
			document.getElementById(tabName).className = 'tab_' + tabName + '_active';
	}
}

function MM_preloadImages()
{
	var d=document;
	if(d.images)
	{
		if(!d.MM_p)
			d.MM_p = new Array();
		var a=new Array('./images/home_active.png', './images/home_inactive.png', './images/diensten_active.png', './images/diensten_inactive.png', './images/portfolio_active.png', './images/portfolio_inactive.png', './images/referenties_active.png', './images/referenties_inactive.png', './images/support_active.png', './images/support_inactive.png', './images/contact_active.png', './images/contact_inactive.png');
		var i, j=d.MM_p.length;
		for(i=0; i<a.length; i++)
		{
			if (a[i].indexOf("#")!=0)
			{
				d.MM_p[j] = new Image;
				d.MM_p[j++].src = a[i];
			}
		}
	}
}

function doResize()
{
	document.getElementById('text_content').style.height = (document.body.clientHeight - 274)+'px';
}

function checkContactForm()
{
	var formObj = document.forms['contact'];

	if(isLeeg(formObj.elements['naam'].value))
	{
		alert("Er is geen naam ingevuld.");
		formObj.elements['naam'].focus();
		return false;
	}

	if(isLeeg(formObj.elements['email'].value))
	{
		alert("Er is geen emailadres ingevuld.");
		formObj.elements['email'].focus();
		return false;
	}

	if(!geldigeEmail(formObj.elements['email'].value))
	{
		alert("Het emailadres is onjuist.");
		formObj.elements['email'].focus();
		return false;
	}

	if(isLeeg(formObj.elements['vraag'].value))
	{
		alert("Er is geen vraag ingevuld.");
		formObj.elements['vraag'].focus();
		return false;
	}
}

// Controleer of invoer voldoet als een geldig emailadres
function geldigeEmail(strInvoer)
{
	// Stel filter in
	//var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

	// Test invoer
	if (filter.test(strInvoer))
		return true; // Invoer correct, return true
	else
		return false; // Invoer niet correct, return false
}

// Controle of de invoer leeg of alleen spaties bevat
function isLeeg(strInvoer)
{
	if (strInvoer.match(/^\s+$/) || strInvoer == "")
	{
		return true;
	}
	else
	{
		return false;
	}
}