<!--
function checkGuestBook()
{
var content = trim(document.GuestBook.content.value);
var verify_Safecode = trim(document.GuestBook.verify_Safecode.value);
          if(content == "") {
		    alert("请输入留言内容！");
			document.GuestBook.content.focus();
		    return false;
		  } 
  if (content.length < 5) {
    alert("留言内容不少于5个字！");
    document.GuestBook.content.focus();        
	return false;
} 
		  if(verify_Safecode == "") {
		    alert("请输入验证码！");
			document.GuestBook.verify_Safecode.focus();
		    return false;
		  } 
     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;
   } 

//-->