function checkform() { // voor zoekform
	if (Trim(document.getElementById('zoekinput').value) == '') {
		alert('U dient een zoekcriterium op te geven.');
		document.getElementById('zoekinput').focus();
		return false;
	}
	else {
		return true;
	}
}

function Trim(TRIM_VALUE){
	if(TRIM_VALUE.length < 1){
		return"";
	}
	
	TRIM_VALUE = RTrim(TRIM_VALUE);
	TRIM_VALUE = LTrim(TRIM_VALUE);
	
	if(TRIM_VALUE==""){
		return "";
	}
	else{
		return TRIM_VALUE;
	}
}

function RTrim(VALUE){
	var w_space = String.fromCharCode(32);
	var v_length = VALUE.length;
	var strTemp = "";
	
	if(v_length < 0){
		return"";
	}
	
	var iTemp = v_length -1;
	
	while(iTemp > -1){
		if(VALUE.charAt(iTemp) == w_space){
		}
		else{
			strTemp = VALUE.substring(0,iTemp +1);
			break;
		}
		iTemp = iTemp-1;
	}

	return strTemp;
}

function LTrim(VALUE){
	var w_space = String.fromCharCode(32);
	
	if(v_length < 1) {
		return"";
	}
	
	var v_length = VALUE.length;
	var strTemp = "";

	var iTemp = 0;

	while(iTemp < v_length){
		if(VALUE.charAt(iTemp) == w_space){
		}
		else{
			strTemp = VALUE.substring(iTemp,v_length);
			break;
		}
		iTemp = iTemp + 1;
	}

	return strTemp;
}

function checkcontact(f){ 
	var reEmail = /^.+\@.+\..+$/ 
	var reTel = /^(-|\+|\d|\s){9,30}$/; 
	var rePC = /^(\d\d\d\d\s?[A-Za-z][A-Za-z]|[A-Za-z]\s?\d\d\d\d)$/; 
	var reSpace=/^\s+$/; 
	var error = false;	
	
	for(var i=0;i<f.length;i++){ 
          if(typeof(f.elements[i].mandatory)=='string' && f.elements[i].type!='checkbox' && f.elements[i].type!='radio'){ 
          	   f.elements[i].style.border = '0px';
          	
               switch(f.elements[i].mandatory){ 
                    case '1':  
                         if(reSpace.test(f.elements[i].value) || f.elements[i].value.length==0){ 
                         	f.elements[i].style.border = '1px solid red';
                         	error = true;
                         } 
                         ;break; //algemeen 
                    case '2':  
                         if(!reEmail.test(f.elements[i].value)){
                         	  f.elements[i].style.border = '1px solid red';
                              error = true;
                         } 
                         break; //email 
                    case '3':  
                         if(!rePC.test(f.elements[i].value)){ 
                         	  f.elements[i].style.border = '1px solid red';
                              error = true;
                         } 
                         break; //pc 
                    case '4':  
                         if(!reTel.test(f.elements[i].value)){ 
                         	  f.elements[i].style.border = '1px solid red';
                              error = true;
                         } 
                         break; //tel 
                    default: break;
               } 
          } 
     } 
     
     if (error) {
     	alert('Vul het gemarkeerde veld in.');
	    return false; 
	 }
	 else {
     	return true; 
	 }
}