function displayForm(id){
  
  var obj = document.getElementById('msgform' + id);
  if(obj.style.display == 'none'){
    obj.style.display = 'block';
  }else{
    obj.style.display = 'none';
  }
}

function checkForm(){
  var obj_name = document.getElementById('name');
  var obj_email = document.getElementById('email');
  var obj_cate = document.getElementById('cate');
  var obj_vcode = document.getElementById('v_code');
  var obj_message = document.getElementById('message');
  
  if(obj_name.value == ''){
    alert('請輸入姓名');
    obj_name.focus();
    return false;
  }
  
  if(obj_name.value.length > 100){
    alert('請勿輸入太長的姓名');
    obj_name.focus();
    return false;
  }

  if(obj_email.value == ''){
    alert('請輸入Email');
    obj_email.focus();
    return false;
  }
  
  var reg_email = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
  if(!reg_email.test(obj_email.value)){
    alert('Email格式錯誤');
    obj_email.focus();
    return false;
  }
  
  if(obj_cate.value == ''){
    alert('請選擇留言分類');
    obj_cate.focus();
    return false;
  }
  
  if(obj_vcode.value == ''){
    alert('請輸入驗證碼');
    obj_vcode.focus();
    return false;
  }
  
  if(obj_message.value == ''){
    alert('請輸入留言內容');
    obj_message.focus();
    return false;
  }
  
  if(obj_message.value.length > 1000){
    alert('請長話短說');
    obj_message.focus();
    return false;
  }
  
  createCookie('tmp_name', escape(obj_name.value), 1);
  createCookie('tmp_email', escape(obj_email.value), 1);
  createCookie('tmp_url', escape(document.getElementById('url').value), 1);
  createCookie('tmp_msg', escape(obj_message.value), 1);
  return true;
  
}

function createCookie(name,value,hours) {
	if (hours) {
		var date = new Date();
		date.setTime(date.getTime()+(hours*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
	var nameEQ = name + "=";
	var ca = document.cookie.split(';');
	for(var i=0;i < ca.length;i++) {
		var c = ca[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
	}
	return '';
}

function eraseCookie(name) {
	createCookie(name,"",-1);
}