LightResults.Extensions.ExceptionHandling 8.0.2

LightResults Extensions

Extensions for LightResults, an extremely light and modern Operation Result Pattern library for .NET.

ExceptionHandling

Provides extension methods for exception handling using LightResults.

Documentation

Make sure to read the docs for the full API.

Try method

The Try method will wrap the execution of an Action or Func in a try { } catch { } block. If an exception occurs, a failed result will be returned and the Exception will be added to the result as metadata.

With an Action

var result = action.Try();
if (result.IsSuccess)
{
    // Do something
}

With an Action with arguments

var result = action.Try(42);
if (result.IsSuccess)
{
    // Do something
}

With a Func

var result = func.Try();
if (result.IsSuccess)
{
    var value = result.Value;
    // Do something
}

With a Func with arguments

var result = func.Try(42);
if (result.IsSuccess)
{
    var value = result.Value;
    // Do something
}

Using the Try method with methods

Although extension methods for Action or Func cannot be attached to ordinary methods, the compiler will automatically cast ordinary methods to Action or Func if only the method name is manually passed as the argument to the extension method.

There are two ways this can be achieved, both of which are explained below.

Using the static class name

using LightResults.Extensions.ExceptionHandling;

public class OrdinaryClass
{
    public void OrdinaryMethod() { }
    public void TryOrdinaryMethod()
    {
        var result = ExceptionHandler.Try(OrdinaryMethod);
        if (result.IsSuccess)
        {
            // Do something
        }
    }
    
    public void OrdinaryMethodWithArguments(int arg1, int arg2) { }
    public void TryOrdinaryMethodWithArguments()
    {
        var result = ExceptionHandler.Try(OrdinaryMethodWithArguments, 1, 2);
        if (result.IsSuccess)
        {
            // Do something
        }
    }

    public int OrdinaryMethodWithReturn() { return 0; }
    public void TryOrdinaryMethodWithReturn()
    {
        var result = ExceptionHandler.Try(OrdinaryMethodWithReturn);
        if (result.IsSuccess)
        {
            var value = result.Value;
            // Do something
        }
    }

    public int OrdinaryMethodWithReturnAndArguments(int arg1, int arg2) { return arg1 + arg2; }
    public void TryOrdinaryMethodWithReturnAndArguments()
    {
        var result = ExceptionHandler.Try(OrdinaryMethodWithReturnAndArguments, 1, 2);
        if (result.IsSuccess)
        {
            var value = result.Value;
            // Do something
        }
    }
}

Declaring a using static statement

using static LightResults.Extensions.ExceptionHandling.ExceptionHandler;

public class OrdinaryClass
{
    public void OrdinaryMethod() { }
    public void TryOrdinaryMethod()
    {
        var result = Try(OrdinaryMethod);
        if (result.IsSuccess)
        {
            // Do something
        }
    }
    
    public void OrdinaryMethodWithArguments(int arg1, int arg2) { }
    public void TryOrdinaryMethodWithArguments()
    {
        var result = Try(OrdinaryMethodWithArguments, 1, 2);
        if (result.IsSuccess)
        {
            // Do something
        }
    }

    public int OrdinaryMethodWithReturn() { return 0; }
    public void TryOrdinaryMethodWithReturn()
    {
        var result = Try(OrdinaryMethodWithReturn);
        if (result.IsSuccess)
        {
            var value = result.Value;
            // Do something
        }
    }

    public int OrdinaryMethodWithReturnAndArguments(int arg1, int arg2) { return arg1 + arg2; }
    public void TryOrdinaryMethodWithReturnAndArguments()
    {
        var result = Try(OrdinaryMethodWithReturnAndArguments, 1, 2);
        if (result.IsSuccess)
        {
            var value = result.Value;
            // Do something
        }
    }
}

Getting the Exception

var result = action.Try();
if (result.IsFailed)
{
    var ex = (Exception)result.Error.Metadata["Exception"];
    // Do something with the base exception type or...
    
    if (ex is ArgumentNullException argumentNullException)
    {
        // Do something with a specific exception type
    }
}