Output Parameters
Closely related to reference parameters are output parameters. Conceptually, they serve as additions to the single “return channel” provided by a method’s return type. By using the out
modifier, you can create such a method:
static bool TrySqrt(int input, out double root){ root = 0.0; // Will learn a in while why this is needed if (input < 0) return false; root = Math.Sqrt(input); return true;}
In this example, we use the return type to denote success or failure, while the output parameter will receive the result in case of success. This is a common pattern for various Base Class Library (BCL) types such as numeric value types that have a TryParse
method:
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