// Bepaal in de querystring de value behorende tot de opgegeven key.
function GetQueryString(key)
{
	var queryString = window.location.search.substring(1);
	var entries = queryString.split('&');

	for (index = 0; index < entries.length; index++)
	{
		var entry = entries[index].split('=');

		if (entry[0] == key)
			return entry[1];
	}
}

// Toon of verberg het gespecificeerde element.
function ToggleDisplay(strElementId, strState)
{
	var element = document.getElementById(strElementId);
	with (element.style)
		if (strState != undefined)
			display = strState;
		else
			if (display == 'none')
				display = '';
			else
				display = 'none';
}