Multi-variable switch statement in C#

Question

I would like use a switch statement which takes several variables and looks like this:

switch (intVal1, strVal2, boolVal3)
{
   case 1, \"hello\", false:
            


        

Answer 1

I do this kind of thing with lists or arrays. If you can enumerate the possible conditions (which you obviously can if you're wanting to do a multi-value switch), then build a lookup table with a multi-part key and an Action or Func as the value.

A simple version would use a Dictionary:

class LookupKey: IComparable
{
    public int IntValue1 { get; private set; }
    public int IntValue2 { get; private set; }
    public bool BoolValue1 { get; private set; }
    public LookupKey(int i1, int i2, bool b1)
    {
        // assign values here
    }
    public int Compare(LookupKey k1, LookupKey k2)
    {
        return k1.IntValue1 == k2.IntValue1 &&
               k1.IntValue2 == k2.IntValue2 &&
               k1.BoolValue1 == k2.BoolValue1;
    }
    public int GetHashCode()
    {
        return (19 * IntValue1) + (1000003 * IntValue2) + (BoolValue1) ? 0 : 100000073;
    }
    // need to override Equals
}

And your dictionary:

static readonly Dictionary> LookupTable;

You can then populate the dictionary at startup, and then a lookup becomes a simple matter of:

Action