mongodb javascript foreach使用方法

 if dbman=nil then dbman:=tdbmanage.create;
 code:=tbsoncodewscope.Create('function(){var str="1111";db.testc.find().forEach(function(x){str=str+ x.name});return str}',bson([]));
 buf:=tbsonbuffer.Create;
 buf.append('eval',code);

function()
{
  var str="1111";
  db.testc.find().forEach
 (
     function(x)
    {
       x.users.forEach
      (
         function(y)
        {
           str=str+y.fetch().name+'!!';
        }
       )
        }
 );
  return str;
}

function()
{
  var str="1111";
  db.testc.find().forEach
 (
     function(x)
    {
       x.users.forEach
      (
         function(y)
        {
          var b=y.fetch();
          if (b!=null)
           str=str+b.name+'!!';
        }
       )
        }
 );
  return str;
}