function submitForm(){
	if(submitForm_validate()){
		var arr = document.getElementsByTagName("input");
           	for(var i = 0; i < arr.length; i ++){
               		var el = arr[i];
                	if(el.name == "__VIEWSTATE"){
                		el.parentNode.removeChild(el);
                	}
           	}

		var f = document.forms[0];
		f.action = "SubmitForm.aspx";
		var hf = submitForm_hasFile();
		//alert(hf);
		//alert(f.encoding);
		//alert(f.enctype);
		
		if(hf){
			f.enctype="multipart/form-data";
			f.encoding = "multipart/form-data"; // IE likes this 
		}
		//alert(f.enctype);
		//alert(f.getAttribute("enctype"));
		//alert(f.encoding);
		
		f.submit();
	}
}
function submitForm_validate(){
	var arr = document.getElementsByTagName("input");
	for(var i = 0; i < arr.length; i ++){
		var el = arr[i];
		if(el.getAttribute("required") == "yes"){
			if(!el.value){
				alert("field '" + el.name + "' is required.");
				return false;
			}
		}
	}
	return true;
}
function submitForm_hasFile(){
	//alert("hasFile...");
	var arr = document.getElementsByTagName("input");
	for(var i = 0; i < arr.length; i ++){
		var el = arr[i];
		//alert(el);
		
		//console.log(el, el.type);
		if(el.type == "file") return true;
	}
	return false;
}