Async version of JSCall

[SantoshGnostice]

I am looking for server side method which can invoke a JavaScript function that takes a callback and later asynchronously calls this callback which should result in a server-side call. Basically an async version of existing JSCall method which can take an anonymous function or a delphi callback. Is there such a method already present?

[Sherzod]

Hi,

 

If I understand you correctly, you can use ajaxRequest (client side) and OnAjaxEvent (server side)

 

You can find a lot of posts on this topic on the forum

 

Best regards,

[SantoshGnostice]

A simple example of what I am looking for:

 

Server-side:

procedure CallBack(AResult: string);
begin
  // Control comes here after timeout
end;

JSAsyncCall('method', CallBack);

Client-side (JS):

method: function(callback) {
  setTimeout(callback, 1000, 'result');
}

I could use ajax to achieve this but I'd have to maintain a mapping on the server of all the callback functions and call them appropriately when the message arrives from the client. I am sure UniGUI must have solved this problem already - so I was looking to see if the framework has something I can use to achieve this.

[SantoshGnostice]

Hi

 

Just checking if there is anything to use for the above situation? Calling an async JS function from the server and getting response from it?

[SantoshGnostice]

I have found an example implementation in UniGUI that may suit what I am looking for. The method "uniGUIDialogs.Prompt" takes a callback function which is called from the client-side once the user dismisses the dialog. Is there something similar which we can use when developing a custom component? How is the the Delphi callback procedure linked to the client-side callback?

[Farshad Mohajeri]

You can achieve this by calling a JS method using server side method JSCall() and on client side your method will cast an ajaxRequest() call which will be handled in OnAjaxEvent Delphi handler.

[SantoshGnostice]

Yes, thank you. I have started working in that direction.