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c# - TryParse with out var param

A new feature in C# 6.0 allows to declare variable inside TryParse method. I have some code:

string s = "Hello";

if (int.TryParse(s, out var result))
{

}

But I receive compile errors: enter image description here

What I am doing wrong? P.S.: in project settings C# 6.0 and .NET framework 4.6 are set.

See Question&Answers more detail:os

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by (71.8m points)

A new feature in C# 6.0 allows to declare variable inside TryParse method.

Declaration expressions was cut from C# 6.0 and wasn't shipped in the final release. You currently can't do that. There is a proposal for it on GitHub for C# 7 (also see this for future reference).

Update (07/03/2017)

With the official release of C#7, the following code compiles:

string s = "42";

if (int.TryParse(s, out var result))
{
     Console.WriteLine(result);
}

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