General method for executing any method with 1 retry using delegates

Question

I am trying to develop a mechanism by which I can execute any method with an attempt to retry.

A repeat will be triggered if an exception is encountered on the first run.

The basic idea: I will have a general class for repeat logic, and I want to pass any method in it through delegates. And this method will be executed with 1 repetition.

So far I have developed it.

public class RetryHandler
{
    Delegate _methodToRetry;

    // default constructor with delegate to function name.
    public RetryHandler(Delegate MethodToExecuteWithRetry)
    {
        _methodToRetry = MethodToExecuteWithRetry;
    }

    public void ExecuteWithRetry(bool IsRetryEnabled)
    {
        try
        {
            _methodToRetry.DynamicInvoke();
        }
        catch (Exception ex)
        {
            if (IsRetryEnabled)
            {
                // re execute method.
                ExecuteWithRetry(false);
            }
            else
            {
                // throw exception
                throw;
            }
        }

    }


}

Now I have a problem:

The methods that I want to transfer have different input parameters (both in the number of parameters and in the types of objects) and different output parameters.

Is there any way I can achieve this? Basically I want to call such methods:

RetryHandler rh = new RetryHandler(MyMethod1(int a, int b));
int output = (int) rh.ExecuteWithRetry(true);

RetryHandler rh2 = new RetryHandler(MyMethod2(string a));
string output2 = (string) rh2.ExecuteWithRetry(true);

Any help would be greatly appreciated. Thank.

Answer 1

• :

     public void ExecuteWithRetry(bool IsRetryEnabled, params object[] args)
      {
          try
          {
              _methodToRetry.DynamicInvoke(args);
          }
          catch (Exception ex)
          {
              if (IsRetryEnabled)
              {
                  // re execute method.
                  ExecuteWithRetry(false, args);
  

  : int output = (int) rh.ExecuteWithRetry(true, a, b);

• rwrite RetryHandler , :

  public static TReturn ExecuteWithRetry<TReturn, TParam>(bool IsRetryEnabled, Func<TParam, TReturn> func, TParam param)
  {
      // ...
      return func(param);
      // ...
  }
  

• , :

  var f = new Func<int, int>((a) => a + 1);
  f.ExecuteWithRetry(x);
  

  :

  public static class Ext
  {
      public static TReturn ExecuteWithRetry<TReturn, TParam>(this Func<TParam, TReturn> func, TParam param)
      {
          return func(param);
      }
  }
  

Answer 2

:

public T Retry<T>(Func<T> func)
{
    try { return func(); }
    catch { return func(); }
}

-, :

public int Test(int a, int b) => a + b;
public string Test(string a) => a + a;

void Example()
{
    Console.WriteLine(Retry(() => Test(1, 2)));
    Console.WriteLine(Retry(() => Test("a")));
}