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How to handle and collect errors in loops. Error log. (NAV/BC)

What if we have a loop in which some actions occur that can cause an error. What if we need to continue iterating through the loop after the errors and save the errors to the log? Today I will show you how this can be done even for transactional operations.

TryFunction

There is a special built-in mechanism for catching errors called TryFunction. The mechanism for working with it is already well described in the documentation, but there is an important exception where TryFunction simply does not work. Database write transactions in try methods just don't work.
This means that these functions cannot be used for try methods:

Handle errors in write transactions

But there is still an easy way to get around this limitation and handle errors even with write transactions. To do this, we can use a separate codeunit with a process call on OnRun. For example, there is a function with a loop that calls a separate codeunit: 

local procedure SimulateErrors()
var
  RunProcess: Codeunit "EL Run Process";
  HasError: Boolean;
  i: Integer;
begin
  for i := 1 to 30 do begin
    ClearLastError();
    RunProcess.SetParams(GetOneOrTwo());
    HasError := not RunProcess.Run();
    if HasError then
      InsertErrorLog();
    Commit();
  end;
end;
The codeunit itself has a simple structure:

codeunit 70300 "EL Run Process"
{
    trigger OnRun()
    begin
        InsertRecord();
    end;

    procedure SetParams(RandomInt: Integer)
    begin
        gRandomInt := RandomInt;
    end;

    local procedure InsertRecord()
    var
        SimulateTransaction: Record "EL Simulate Transaction";
    begin
        SimulateTransaction.Init();
        case gRandomInt of
            1:
                SimulateTransaction."Is Insert" := false;
            2:
                SimulateTransaction."Is Insert" := true;
        end;
        SimulateTransaction.Insert(true);
    end;

    var
        gRandomInt: Integer;
}
A possible error in the process is processed with a probability of 50%, depending on the "Is Insert" field:

trigger OnInsert()
begin
  Rec.TestField("Is Insert");
end;
As a result, we get a complete log of errors in write transactional processes:

Source code

MONDAY, May 24, 2021
Author: Volodymyr Dvernytskyi