Check if value tuple is default

c# c#-7.2 valuetuple
nawfal picture nawfal · Apr 30, 2018 · Viewed 14.2k times · Source

How to check if a System.ValueTuple is default? Rough example:

(string foo, string bar) MyMethod() => default;

// Later
var result = MyMethod();
if (result is default){ } // doesnt work

I can return a default value in MyMethod using default syntax of C# 7.2. I cannot check for default case back? These are what I tried:

result is default
result == default
result is default(string, string)
result == default(string, string)

Answer

Gibbon picture Gibbon · Apr 30, 2018

If you really want to keep it returning default, you could use

result.Equals(default)

the built-in Equals method of a ValueTuple should work.

As of C# 7.3 value tuples now also support comparisons via == and != fully, Meaning you can now also do

result == default and it should work the same.

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