function Show_button_save(k)
	{ 
		if (( k > 18 ) || (k == 8)) 
		{
			if (document.all.save_check) document.all.save_check.src='image/save.PNG'; 
			if (document.all.savebutton_check) document.all.savebutton_check.disabled=false;
		}
	}

	function numonly(toets)
	{ 
		return ((toets > 47) && (toets < 58));
	}

	function only_eva(toets)
	{ 
		return (((toets > 48) && (toets < 54))  | (toets == 46 ));
	}
	function loweronly(toets)
	{ 
		return ((toets > 96) && (toets < 123)); 
	}

	function checkValue(v,min,max) {
		if (( v < min) || (v > max )) {
			alert('Ongeldig, waarde moeten tussen '+min+' en '+max+' liggen.'); v.value=''; return false;
		}
	}

	function checkuniekemailadres(index,email) {

		var f = 0

		var form = window.document.forms[0];

		for (var i = 0; i < form.elements.length; i ++ ) {
			
			if ( (form.elements[i].isemail == 1) && (form.elements[i].value==email.value) && (form.elements[i].index != index) ) {
				f = 1;
			}
		}		

		if (f == 1) {
			alert('Een email adres kan maar één keer worden gebruikt.');
			email.value = '';
			return false;
		}
	}

	function Validatie ()
	{
	
		var t = 0
		var f = 0

		var form = window.document.forms[0];

		for (var i = 0; i < form.elements.length; i ++ ) {
			if ( (form.elements[i].value == "") && (form.elements[i].v=="T") ) {
				t += 1;
				if (t == 1) { f = i }
			}
		}

		if (t > 0) {

			if ( t == 1 ) {
				var s = "is";
			} else {
				var s = "zijn";
			}

			alert(t + " van de verplichte velden "+s+" niet of onjuist ingevuld.");
			while (window.document.forms[0].elements[f].type == "hidden") {
				f++;
			}

			window.document.forms[0].elements[f].focus();
			return false;

		} else {
			return true;
		}
	}

	function TimeOnly(toets)
	{
		return (((toets > 47) && (toets <= 58)) || (toets == 46) );
	}

	function DateOnly(toets)
	{
		return (((toets >= 48) && (toets < 58)) || (toets == 45) );
	}

	function CheckTime(v)
	{
		var t = 0
		var p = 0	
		var uur,min
		var b = true

		for (var i = 0 ; i < v.value.length ; i++) {
			if ( (v.value.substring(i,i+1) == ":") || (v.value.substring(i,i+1) == ".") ) {
				if (p == 0) { p = i }
				t = t + 1;
				if ( t > 1 ) { b = false;}
			}
		}

		if ( p != 0 ) {
			uur = v.value.substring(0,p);
			min = v.value.substring(p+1,p+3);
			if ( min.length == 0 ) { min = min + "00"; } 
			if ( min.length == 1 ) { min = "0" + min ; } 
		}
		else {


			if (v.value.length == 4) {
				uur = v.value.substring(0,2);
				min = v.value.substring(2,4);
			}
			else {		
				uur = v.value;
				min = "00";
			}

			if (v.value.length > 4) {b = false;}
		}


		if ( ( uur > 23 ) || ( min > 60) || ( b == false ) ) { 
			alert("ongeldige tijd.");
			v.value = "" 
			b = false;
		}
		else {
			v.value = uur + ":" + min;
		}

		return b;
	}

	function CheckDate (v) {
		var d,m,j
		var p1 = 0 
		var p2 = 0
		var t = 0
		var b = true;
		var tmp = ""

		if ( (v.value) && (v.value.length == 6) && (v.value.substring(1,2) != "-") ) {
			tmp += v.value.substring(0,2) + "-"
			tmp += v.value.substring(2,4) + "-"
			tmp += v.value.substring(4,6)
			v.value = tmp
		}

		for (var i = 0 ; i < v.value.length ; i++) {
			if (v.value.substring(i,i+1) == "-") {
				if (p1 == 0) { p1 = i }
				else if (p2 == 0) { p2 = i }
				t = t + 1;
				if ( t > 2 ) { b = false;}
			}
		}

		if ( t != 2 ) { b = false; }
		if ( v.value == "--" ) { b = false; }

		d = v.value.substring(0,p1);
		m = v.value.substring(p1+1,p2);
		j = v.value.substring(p2+1,p2+3);

		if ( (d < 1) || (m < 1) || (d > 31) || (m > 12) || (b == false) || (d.length == 0) || (m.length == 0) || (j.length == 0) ) {
			alert("ongeldige datum.");
			v.value=""
			b = false;
		} else {
			if (d.length == 1) { d = "0" + d }
			if (m.length == 1) { m = "0" + m }
			if (j.length == 1) { j = "0" + j }
			v.value = d + "-" + m + "-" + j
		}

		return b;
	}
	function CheckDate_EmptyIsValid (v) {
		var d,m,j
		var p1 = 0 
		var p2 = 0
		var t = 0
		var b = true;
		var tmp = ""

		if ( (v.value) && (v.value.length == 6) && (v.value.substring(1,2) != "-") ) {
			tmp += v.value.substring(0,2) + "-"
			tmp += v.value.substring(2,4) + "-"
			tmp += v.value.substring(4,6)
			v.value = tmp
		}

		for (var i = 0 ; i < v.value.length ; i++) {
			if (v.value.substring(i,i+1) == "-") {
				if (p1 == 0) { p1 = i }
				else if (p2 == 0) { p2 = i }
				t = t + 1;
				if ( t > 2 ) { b = false;}
			}
		}

		if ( t != 2 ) { b = false; }
		if ( v.value == "--" ) { b = false; }

		d = v.value.substring(0,p1);
		m = v.value.substring(p1+1,p2);
		j = v.value.substring(p2+1,p2+3);

		if ( (d < 1) || (m < 1) || (d > 31) || (m > 12) || (b == false) || (d.length == 0) || (m.length == 0) || (j.length == 0) ) {
			alert("ongeldige datum.");
			v.value=""
			b = false;
		} else {
			if (d.length == 1) { d = "0" + d }
			if (m.length == 1) { m = "0" + m }
			if (j.length == 1) { j = "0" + j }
			v.value = d + "-" + m + "-" + j
		}

		return b;
	}

	function CheckEmail(v) {
		b = ((v.value.indexOf("@") != -1) && (v.value.indexOf(".") != -1));

		if (v.value.length == 0) b = true;

		if (!b) {
			alert(v.value+" is een ongeldig email adres");
			v.select();
		}
		return b;
	}
	
	function NewWindow ( url ) {
		m = open(url,"title1",'top=90 ,left=90, width=610 ,height=400, scrollbars=1');
		m.focus();
	}
	function NewWindow_pdf ( url ) {
		m = open(url,"pdfwindow",'resizable=1,top=0 ,left=0, width=1024 ,height=1000, scrollbars=1');
		m.focus();
	}	
	function NewWindow_bar ( url ) {
		m = open(url,"title2",'top=10 ,left=10 ,width=900, height=600 ,scrollbars=1');
		m.focus();
	}
	
	function NewWindow2 ( url ) {
		m = open(url,"title3",'top=80 ,left=70, width=650 ,height=500 ,scrollbars=0');
		m.focus();
	}

	function Check_NietsTeBewaren() { 
		
		if (document.all.savebutton_check) {
			if (document.all.savebutton_check.disabled==true) return true;

			return confirm('Gegevens zijn NIET opgeslagen. Als u op [ok] klikt verliest u uw wijzigingen.\nGegevens niet opslaan ?');
		}
		
		return true;
	}
	
	function closeinfo() {
		document.getElementById('info').style.visibility = 'hidden';
	}
	
	function showinfo() {
		document.getElementById('info').style.visibility = 'visible';
	}