Javascript模拟FORM以POST方式提交表单数据

如何实现Javascript模拟FORM以POST方式提交表单数据呢？

function   AddDataPost(sUserId,sUserName)    
  {  
  var   obj   =   new   ActiveXObject("Microsoft.XMLHTTP");    
   
  sUserId   =   escape(sUserId);  
  sUserName   =   escape(sUserName);    
  var   userInfo   =   "userid="+sUserId+"&username="+sUserName;    
  obj.open("POST","getData.asp",false);    
  obj.setRequestHeader("Content-Type","application/x-www-form-urlencoded")    
  obj.send(userInfo);    
  return   unescape(obj.responseText);  
  }  
   
   
  取值的时候必须用unescape()函数  
   
  <%   @Language="JavaScript"   %>  
  <%  
  var   userId   =   unescape(Request.Form("userid"));    
  var   userName   =   unescape(Request.Form("username"));    
  Response.write("ID:   "+   userId   +";   Name:   "+   userName);  
  %>  


第二种
document.write('<form   name=myForm>');  
  var   myForm=document.forms['myForm'];  
  myForm.action='';  
  myForm.method='POST';  
  myForm.submit();