function check_words_find(theForm) {
var key = trim(theForm.key.value);
var reg = /[`~!@#\$%\^&\*\(\)\[\]\{\}\|\\\/,\.;:\'\"\?<>\+=]+/;
var pattern = new RegExp(reg);

if(key == "") {
alert("请输入搜索关键字！");
theForm.key.focus();
return false;
}
if(key.length<1) {
alert("请输入搜索关键字！");
theForm.key.focus();
return false;
}

if(key.length<2){
alert("您输入的搜索关键字太短！");
theForm.key.focus();
return false;
}

if(key.length>50) {
alert("您输入的搜索关键字太长！");
theForm.key.focus();
return false;
}

if(pattern.test(key)){
alert("搜索关键字不能含有特殊字符！");
theForm.key.focus();
return false;
}
}
function trim(inputString) {
if (typeof inputString != "string") { return inputString; }
var retValue = inputString;
var ch = retValue.substring(0, 1);
while (ch == " ") { 
retValue = retValue.substring(1, retValue.length);
ch = retValue.substring(0, 1);
}
ch = retValue.substring(retValue.length-1, retValue.length);
while (ch == " ") {
retValue = retValue.substring(0, retValue.length-1);
ch = retValue.substring(retValue.length-1, retValue.length);
}
while (retValue.indexOf("  ") != -1) { 
retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length); 
}
return retValue;
}