Check if a variable is in an ad-hoc list of values

Question

Is there a shorter way of writing something like this:

if(x==1 || x==2 || x==3) // do something

Wha

Answer 1

You can create a simple Dictionary that'll be used as a Decision Table for that problem:

        //Create your decision-table Dictionary
        Action actionToPerform1 = () => Console.WriteLine("The number is okay");
        Action actionToPerform2 = () => Console.WriteLine("The number is not okay");
        var decisionTable = new Dictionary
            {
                {1, actionToPerform1},
                {2, actionToPerform1},
                {3, actionToPerform1},
                {4, actionToPerform2},
                {5, actionToPerform2},
                {6, actionToPerform2}
            };

        //According to the given number, the right *Action* will be called.
        int theNumberToTest = 3;
        decisionTable[theNumberToTest](); //actionToPerform1 will be called in that case.

Once you've initialized your Dictionary, all left to do is:

decisionTable[theNumberToTest]();