Dealing with an array in a posted body (on the server side)

[HalcyonLogic]

Danijel,

Trying to understand an array concept on the server side and was hoping you could point me in the right direction.

Let's say I have a javascript function that returns, amongst other things, a JSON array of values using a POST (not a GET), so values will be in the body not the header.

Ex: CompanyName = ACME    <--- Simple/single value followed by
     Employees[ "Mike", "Suzan", "Danijel", "Richard" ]    <--- array

Body example/source form data:
CompanyName=ACME&Employees%5B%5D=Mike&Employees%5B%5D=Suzan&Employees%5B%5D=Danijel&Employees%5B%5D=Richard

How do I get it back on the server side using a TrtcDataProvider.OnDataReceived event? How can I iterate though the elements of the employees array?

procedure TCompanyDM.RtcDataProvider_GetEmployeesOnDataReceived( Sender: TRtcConnection );
var
  Srv:TRtcDataServer absolute Sender;
  EmployeeIndex: Integer;
  CompanyName: String;
begin
  if Srv.Request.Complete then
  begin
      Srv.Request.Params.AddText( Srv.Read );

     CompanyName := Srv.Request.Params[ 'CompanyName ' ] ;  // This I get Ok, I get this value

     Srv.Request.Params[ 'Employees' ] ; // <--- However, this I don't, how do I get this array, how do I read it's properties/elements? Seems to be empty.

     for EmployeeIndex := 0 to do
     begin
             
     end;

      // Do something with it

      Srv.Response.Status( 200, 'Successfull' );
      Srv.Response.ContentType := 'application/javascript';
  end;
end;

Perhaps I am going about it the wrong way, please include sample code if possible.

Thanks in advance,
Richard

[Kevin Powick]

The format of your data seem a little odd.  You essentially have an array in the post body named Employees[], with the values Mike, Suzan, Danijel, and Richard.

Nonetheless, you could try using the .Element and .ElementCount methods.

Count := Request.Params.ElementCount['ElementName']
value := Request.Params.Element['ElementName', ndx];

Code:

for ndx :=0 to Request.Params.ElementCount['Employees[]'] - 1 do
  begin
    Employee := Request.Params.Element['Employees[]', ndx];
    // Do something...
  end;

[HalcyonLogic]

Thanks for the tip Kevin, however, using your sample code, the elementcount is always zero.

As for the array looking a bit odd, isn't it the recommended way of posting array as described here?
http://api.jquery.com/jquery.post/

See:
Example: Pass arrays of data to the server (while still ignoring the return results).
$.post("test.php", { 'choices[]': ["Jon", "Susan"] });

[Kevin Powick]

In your original post you show the contents of the POST body.  Where did you get that?  Is that from Request.Params.Text?  If not, please post the values from Request.Params.Text

[HalcyonLogic]

Kevin would you be king enough to have a look at this example I have prepared:

http://jsfiddle.net/Yx6N7/1/

Follow the instruction at the top, you'll see how I came up with this structure.

Kind Regards,
Richard

[Kevin Powick]

I still think you should post exactly what is received by RTC.  Please post results of Request.Params.Text so that you can see exactly with what you are dealing.

[HalcyonLogic]

Here is my Srv.Request.Params.Text:
(The reference to "Employees" was just as an example, I am actually dealing with a "Taxes" array:


AccountID=12&Amount=100&Date=2013-05-28&Taxes%5B%5D=18&Taxes%5B%5D=19&Desc=asdaad&SessionID=2602CC5A9E894DFEA92B13601627DEEA

[Kevin Powick]

Perhaps the issue is that the data is still URL Encoded.  The %5B and %5D are brackets "[]".  Have you tried the URL_Decode() function on the data prior to processing?

To expand on my original code, including the URL_Decode() function;

Code:

procedure TMyServer.UpdateStuff(const DS: TRtcDataServer);
var
   ndx: integer;
   Tax: string;
begin

  DS.Request.Params.AddText(DS.Read);
  if not (DS.Request.Complete) then exit;

  DS.Request.Params.Text := URL_Decode(DS.Request.Params.Text);    
  for ndx :=0 to DS.Request.Params.ElementCount['Taxes[]'] - 1 do
  begin
    Tax := Request.Params.Element['Taxes[]', ndx];
    // Do something...
  end;
end;

[HalcyonLogic]

Kevin, you hit the nail on the head!

That's what's going on, I have tried adding URL_Decode and now it all works.

In summary, your 2 part answer solved it:

1. Needed a URL_Decode and
2. Needed the loop mentioned above to iterate through the elements.

Can't thank you enough for taking the time to help me with this.

Kind Regards,
Richard

[Kevin Powick]

Good news.  Glad I could help.

Cheers,

Kevin