SQL SERVER data source venet handler

Sience this application is presented as a low code app., please advise me why when I tried to create an "on click event" i get the error
"dotnet: Pages\AddExportInboundCommand.razor.designer.cs(161,21): error CS0246: The type or namespace name 'UspInboundExportCalculation' could not be found (are you missing a using directive or an assembly reference?) [D:\MyProjects\test\server\BcrsfWebApp.csproj]"
Where should I set the directive or the assembly reference?

I'm not sure I understand what exactly you are doing however you might need to use UspInboundExportCalculation type with full name including namespace. Check where this type is declared.

Hello Enchev
I have a store procedure in data base. This was translated by Radzen like in the picture below. I want to acces this method by clicking a button. Can you tell me whar fields to chose from the event handler( none of the information from the documentation is suitable. I get errors like "could not be found (are you missing a using directive or an assembly reference?) "

I want that store procedure to be executed by clicking a button

What is this type then? The stored procedure from your screenshot does not return such value.

It does, this is the whole code
public async Task UspInboundExportCalculations(string ExportInboundCommandid)
OnUspInboundExportCalculationsDefaultParams(ref ExportInboundCommandid);

      SqlParameter[] @params =
          new SqlParameter("@returnVal", SqlDbType.Int) {Direction = ParameterDirection.Output},
          new SqlParameter("@ExportInboundCommandid", SqlDbType.UniqueIdentifier) { Direction = ParameterDirection.Input, Value = new Guid(ExportInboundCommandid)},
      context.Database.ExecuteSqlRaw("EXEC @returnVal=[WebApp].[usp_InboundExportCalculation] @ExportInboundCommandid", @params);

      int result = Convert.ToInt32(@params[0].Value);

      OnUspInboundExportCalculationsInvoke(ref result);

      return await Task.FromResult(result);

Again, this procedure returns an int value if the execution is successful or not

This is the procedure method name

Ok, but how can I invoke it and what should I put to Then event?

This procedure does not return any value that can be used by Then action of the event. You can just execute it.

So I chose Execute C#
and at code what should I write?

By execute I mean Invoke Data Source Method action not Execute action.

Just like this?
Without Then?