Methods for Returning Multiple Data Points in C#

In C# you have a number of options available when you need to return more than one value from a method call.

1. Return a complex object containing multiple properties such as a Class or a Struct
2. Return OUT parameters
3. Return Ref parameters
4. Return a tuple

If you already have a Class or Struct defined in your business objects this is an excellent way to go.

When your requirements are more dynamic, and a business object has not already been defined for frequent use, the last three options work nicely.

The Out and Ref parameters are defined in a method input parameters, and then specified as Out or Ref when calling the method. The difference is that with a Ref parameter, you need to initialize it before calling the method, and the method does not have to modify the object sent as a Ref parameter. With an Out parameter, you do not have to initialize the object before the method call. However, the method must set a value for the Out parameter before returning.

The Tuple is a more recent technique utilizing generics. You can define a tuple with any number of data attributes, each having its own unique type definition.

For example, tuple<int, string, double> myTuple defines a complex variable myTuple with three properties. The first property is an int, second a string, and the third a double. This is like creating a class dynamically without naming the properties. The properties are therefore referenced by their ordinal position as myTuple.Item1, etc.

Using a tuple you can create a method returning a complex object that is defined as you define the method, returning the tuple value.

That’s my C# method output review for the year.

Cheers,

Ben