一个正则的问题，求赐教！！！

Question

当gKeyword等于如下的四种情况的时候：
gKeyword = "["; 
gKeyword = "]";
gKeyword = "(";
gKeyword = ")";执行下面的语句报错：
new RegExp("(" + replaceReg(gKeyword) + ")", "g")
//正则表达式转义
function replaceReg(str){
      return str.replace(new RegExp("\\?","gm"),"\\?").replace(new RegExp("\\+","gm"),"\\+").replace(new RegExp("\\)","gm"),"\\)").replace(new RegExp("\\(","gm"),"\\(")
      .replace(new RegExp("\\]","gm"),"\\]").replace(new RegExp("\\[","gm"),"\\[").replace(new RegExp("\\*","gm"),"\\*").replace(new RegExp("\\\\","gm"),"\\\\");      
}当gKeyword = "[" 的时候报错如下：
行: 228
错误: 正则表达式中缺少 ']'如何做才能在gKeyword的值等于这四种情况的时候 不报错呀！！！

Answer 1

<script type="text/javascript">
gKeyword = ["[", "]","(",")","*","\\"];
   for(var i in gKeyword){
    var reg=new RegExp("(\\" + gKeyword[i] + ")", "g");
    var b="[]()*\\";
    alert(gKeyword[i]+":"+reg.test(b));
   }
</script>
这样试试

Answer 2

<script type="text/javascript">
gKeyword = ["[", "]","(",")","*","\\","a"];
function replaceReg(str){
     return str.replace(new RegExp("\\?","gm"),"\\?")
               .replace(new RegExp("\\+","gm"),"\\+")
  .replace(new RegExp("\\)","gm"),"\\)")
  .replace(new RegExp("\\(","gm"),"\\(")
               .replace(new RegExp("\\]","gm"),"\\]")
  .replace(new RegExp("\\[","gm"),"\\[")
  .replace(new RegExp("\\*","gm"),"\\*")
  .replace(new RegExp("\\\\","gm"),"\\\\");  
   }
   for(var i in gKeyword){
    var reg=new RegExp("(\\" + gKeyword[i] + ")", "g");
    var b="[]()*\\a";
    alert(gKeyword[i]+":"+reg.test(b));
   }
</script>
不知这是不是你想要的