function search_dealer_check()
{
	
	
	if(document.form1.postcode.value=="")
	{
		alert("Het veld Postcode moet worden ingevuld");
		document.form1.postcode.focus();
		return false;
	}
	if(isNaN(document.form1.postcode.value)==true)
	{
		alert("Vul enkel de eerste vier cijfers van de postcode in");
		document.form1.postcode.value="";
		document.form1.postcode.focus();
		return(false);
	}
    
        var po=document.form1.postcode.value;
	if(po.length<4)
	{
		alert("Het veld Postcode moet worden ingevuld");
		document.form1.postcode.focus();
		return false;
	}
	/*if(document.form1.email.value=="")
	{
		alert("u moet 4 cijfers van de postcode invullen");
		document.form1.postcode.focus();
		return false;
	}
	i=1;
	var eadd=document.form1.email.value;
	var sLen=eadd.length;
	while((i<sLen)&&(eadd.charAt(i)!="@"))
	{
		i++;
	}
	if((i>=sLen)||(eadd.charAt(i)!="@"))
	{
		alert("Het veld Email moet juist worden ingevuld");
		document.form1.email.value="";
		document.form1.email.focus();
		return false;
	}
	else i+=2;
	
	while((i<sLen)&&(eadd.charAt(i)!="."))
	{
		i++;
	}
	if((i>=sLen-1)||(eadd.charAt(i)!="."))
	{
               	alert("Het veld Email moet juist worden ingevuld");
		document.form1.email.value="";
		document.form1.email.focus();
		return false;
	}
    p1=document.form1.merk[0].checked;
	p2=document.form1.merk[1].checked;
    p3=document.form1.merk[2].checked;
	/*var mlen=document.form1.merk.length;
	for(var ii=0;ii<mlen;ii++)
	{
		if(document.form1.merk[ii].checked)
		{
			var sid1=document.form1.merk[ii].value;
		}
	}
	
alert("hi");
	
	if((!p1)&&(!p2)&&(!p3))
	{
		alert("Minstens 1 merk moet geselecteerd worden.");
		document.form1.merk[0].focus();
		return false;
	}*/
	document.form1.submit();
}