Using blocks in C# switch expression?

Question

I fail to find documentation addressing this issue. (perhaps I am just bad at using google...) My guess is that the answer is negative, however I didn't understand where this is addressed in the documentation. To be precise my question is the following.

Suppose, I want to execute something like this:

DirectoryInfo someDir = new DirectoryInfo(@".\someDir");
Console.WriteLine($"Would you like to delete the directory {someDir.FullName}?");
string response = Console.ReadLine().ToLower();

response switch
{
    "yes" => { someDir.Delete(); ... MoreActions},
     _ => DoNothing()
};

I understand that I can achieve the desired behavior by using the regular switch or if/else, however I was curious whether it is possible to use switch expression in this case.

Answer 1

however I didn't understand where this is addressed in the documentation

This is stated pretty clear here:

There are several syntax improvements here:

• The variable comes before the switch keyword. The different order makes it visually easy to distinguish the switch expression from the switch statement.
• The case and : elements are replaced with =>. It's more concise and intuitive.
• The default case is replaced with a _ discard.
• The bodies are expressions, not statements.

{ someDir.Delete(); ... MoreActions} is not an expression.

However, you can abuse every feature, as they say :)

You can make the switch expression evaluate to an Action, and invoke that action:

Action a = response switch
{
    "yes" => () => { ... },
     _ => () => { .... }
};
a();

You can even reduce this to a single statement:

(response switch
{
    "yes" => (Action)(() => { ... }),
     _ => () => { ... }
})();

But just don't do this...

Answer 2

As per documentation: The bodies are expressions, not statements.

You can do something like this though:

Action fn = response switch
{
    "yes" => () => { BlockTest(); },
     _ => () => { OldTest(); }
};

Answer 3

You can also introduce local function (C# 7.0 and above) and do something like:

response switch
{
    "yes" => DoSomething(),
     _ => DoNothing()
};

void DoSomething()
{
    someDir.Delete();
    ... MoreActions
}