function doSearch() {
	var sch_text = trim(document.txtsearchkey.sch_text.value);

	if(sch_text == "" || sch_text.substring(0,3) =="请输入") {
		alert("提示：请输入关键词！");
		document.txtsearchkey.sch_text.focus();
		return false;
	}
	if (sch_text.length < 2) {
		alert("提示：关键词不能少于2个字符！");
		document.txtsearchkey.sch_text.focus();        
		return false;
	}
	document.txtsearchkey.submit()
	return false;
}

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;
   }