function formCheck(formobj){
	// Enter name of mandatory fields
	var fieldRequired = Array("yourname", "youremail", "friendname", "friendemail");
	
	// Enter field description to appear in the dialog box
	var fieldDescription = Array("Your name", "Your email address", "Your friends name", "Your friends email address");
	
	// dialog message
	var alertMsg = "Please complete the following required fields:\n";
	
	var emailfilter = /^([a-zA-Z0-9_.-])+@([a-zA-Z0-9_.-])+\.([a-zA-Z])+([a-zA-Z])+/;
	
	var l_Msg = alertMsg.length;
	
	for (var i = 0; i < fieldRequired.length; i++){
		var obj = formobj.elements[fieldRequired[i]];
		if (obj){
			switch(obj.type){
			case "select-one":
				if (obj.selectedIndex == -1 || obj.options[obj.selectedIndex].text == ""){
					alertMsg += " - " + fieldDescription[i] + "\n";
				}
				break;
			case "select-multiple":
				if (obj.selectedIndex == -1){
					alertMsg += " - " + fieldDescription[i] + "\n";
				}
				break;
			case "text":
			case "textarea":
				if (obj.value == "" || obj.value == null || obj.value == "Enter your name" || obj.value == "Enter your email address" || obj.value == "Enter your friends name" || obj.value == "Enter your friends email address" ){
					alertMsg += " - " + fieldDescription[i] + "\n";
				}
				if ( obj.id == "youremail" && obj.value != "" && obj.value != "Enter your email address" ){
					if (emailfilter.test(obj.value) == false) {
						alertMsg += " - Your email address is invalid\n";
					}
				}
				if ( obj.id == "friendemail" && obj.value != "" && obj.value != "Enter your friends email address" ){
					if (emailfilter.test(obj.value) == false) {
						alertMsg += " - Friends email address is invalid\n";
					}
				}
				break;
			default:
			}
			if (obj.type == undefined){
				var blnchecked = false;
				for (var j = 0; j < obj.length; j++){
					if (obj[j].checked){
						blnchecked = true;
					}
				}
				if (!blnchecked){
					alertMsg += " - " + fieldDescription[i] + "\n";
				}
			}
		}
	}

	if (alertMsg.length == l_Msg){
		return true;
	}else{
		alert(alertMsg);
		return false;
	}
}