本例中正则表达式不能显示

<script type="javascript">

   var reg_expression=/^ming/;
   var textString="mingrisoft";
   var result=reg_expression.test(textString);
  
   document.write("<font size='+1'>"+result+"<br>");
   
   if(result)
       {
       document.write("正则表达式/^ming/匹配字符串\""+textString+"\".<br>");
       }
   else{
       alert("未找到匹配的模式!");
       }

</script>