function checkQQ(){
	var checkOK = "0123456789";
	var checkStr = form1.guestQQ.value;
	var allValid = true;
	for (i = 0;  i < checkStr.length;  i++){
		ch = checkStr.charAt(i);
		for (j = 0;  j < checkOK.length;  j++)
		if (ch == checkOK.charAt(j))
			break;
		if (j == checkOK.length){
			allValid = false;
			break;
		}
	}
	if (!allValid){
		alert("QQ只能由数字组成！");
		form1.guestQQ.select();
		return (false);
	}
	return (true);	
}

function ChangeImages(){
	document.form1.GuestImages.value=document.form1.selectimages.value;
	document.form1.showimages.src="images/guestbook/"+document.form1.selectimages.value;
}
function form1_onsubmit(){
	if(!NullChk(form1.title,"标题"))
		return false;
	if (form1.title.value.length > 20){
		alert("标题不能超过20个字符！");
		form1.title.focus();
		return (false);
	}
	if(!NullChk(form1.guestname,"真实姓名"))
		return false;	
	if(form1.guestname.value.length<2){
		alert("姓名不能少于两个字！");
		form1.guestname.select();
		return false;
	}
	if(form1.guestQQ.value!=""){
		if(form1.guestQQ.value.length<5){
			alert("老大！QQ最少得5位以上吧!");
			form1.guestQQ.select();
			return false;
		}
		if(form1.guestQQ.value.length>12){
			alert("老大！你见过这长的QQ吗!");
			form1.guestQQ.select();
			return false;
		}
	}
	 if (form1.sheng.value=="--省级--")
	{   alert("城市省级必须选择");
	    form1.sheng.focus();
		return (false);
	}
	if (form1.shi.value=="--市级--")
	{   alert("城市市级必须选择");
	    form1.shi.focus();
		return (false);
	}
	if(form1.guestemail.value!=""){
		if(!isEmail(form1.guestemail.value)){
			alert("Email地址不合法！");
			form1.guestemail.select();
			return false;
		}
	}
	/*var keywords = trim(document.form1.body.value);
	// var direction = document.searchForm.direction.value;

	if(keywords == "") {
		alert("内容不能为空！");
		document.form1.body.focus();
		return false;
	} 
	if (form1.body.value.length > 500){
		alert("评论不能超过500个字符！");
		form1.body.focus();
		return (false);
	}

	if(!NullChk(form1.body,"内容"))
		return false;	
	if(form1.body.value.length>500){
		alert("Sorry,留言信息不能超过500个字！");
		return false;
	}*/
	form1.Submit1.value = "提交中，请稍候..." 
	form1.Submit1.disabled = true;	
	return true;	
}

function trim(inputString) {

  if (typeof inputString != "string") { return inputString; }
  var retValue = inputString;
  var ch = retValue.substring(0, 1);
  while (ch == " ") { 
  //检查字符串开始部分的空格
	  retValue = retValue.substring(1, retValue.length);
	  ch = retValue.substring(0, 1);
  }
  ch = retValue.substring(retValue.length-1, retValue.length);
  while (ch == " ") {
	 //检查字符串结束部分的空格
	 retValue = retValue.substring(0, retValue.length-1);
	 ch = retValue.substring(retValue.length-1, retValue.length);
  }
  while (retValue.indexOf("  ") != -1) { 
 //将文字中间多个相连的空格变为一个空格
	 retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length); 
  }
  return retValue;
}