ResultType

A Proposal of a Result Type in .NET

When to use

This Result Type is useful in scenarios, where you want to mildly enforce checking, if the underlying method has executed successfully. Additionally you will get a cleaner error-handling and reduce the risk of NullReferenceExceptions.

Usage

1. Copy the class definitions from Result.cs and ResultExtensions.cs to your code base and make them accessible publicly.

2. Use Result or Result<T> as return value for all relevant functions:

private Result<Person> GetPersonFromDatabase(Guid id)
{
    try
    {
        return database.GetPersonById(id);
    }
    catch (Exception ex)
    {
        return ex;
    }
}

As you can see, the Result Type also has implicit casts implemented, that will reduce the amount of code needed.

3. Use the .Check() Extension Method to quickly check and throw.

4. Return any thrown exceptions from .Check() without worries about the StackTrace, as it gets preserved.

Features

• Implicit castings allow you to directly return the desired type, which will be casted either to a positive Result<T>, when you return an object of type <T>, or to a negative Result<T> / Result, when you return an Exception object.
• The Extension Method Check() quickly allows you to check if a Result was successfull and throw the underlying exception (while preserving the StackTrace) if it was not.

try
{
    Result result = GetResult().Check();
}
catch (Exception ex)
{
    //Here the Exception includes the StackTrace of all underlying (rethrowing) Methods
    //See StackTraceTest for examples
    logger.LogError(ex.ToString());
}

• Result<T> is inheriting Result, so you can always cast to a normal Result if you don't need the payload <T> anymore.