Multiple cases in switch statement

Solution 1:

I guess this has been already answered. However, I think that you can still mix both options in a syntactically better way by doing:

switch (value)
{
    case 1: case 2: case 3:          
        // Do Something
        break;
    case 4: case 5: case 6: 
        // Do Something
        break;
    default:
        // Do Something
        break;
}

Solution 2:

There is no syntax in C++ nor C# for the second method you mentioned.

There's nothing wrong with your first method. If however you have very big ranges, just use a series of if statements.

Solution 3:

In C# 7 (available by default in Visual Studio 2017/.NET Framework 4.6.2), range-based switching is now possible with the switch statement and would help with the OP's problem.

Example:

int i = 5;

switch (i)
{
    case int n when (n >= 7):
        Console.WriteLine($"I am 7 or above: {n}");
        break;

    case int n when (n >= 4 && n <= 6 ):
        Console.WriteLine($"I am between 4 and 6: {n}");
        break;

    case int n when (n <= 3):
        Console.WriteLine($"I am 3 or less: {n}");
        break;
}

// Output: I am between 4 and 6: 5

Notes:

The parentheses ( and ) are not required in the when condition, but are used in this example to highlight the comparison(s).
var may also be used in lieu of int. For example: case var n when n >= 7:.

Solution 4:

This syntax is from the Visual Basic Select...Case Statement:

Dim number As Integer = 8
Select Case number
    Case 1 To 5
        Debug.WriteLine("Between 1 and 5, inclusive")
        ' The following is the only Case clause that evaluates to True.
    Case 6, 7, 8
        Debug.WriteLine("Between 6 and 8, inclusive")
    Case Is < 1
        Debug.WriteLine("Equal to 9 or 10")
    Case Else
        Debug.WriteLine("Not between 1 and 10, inclusive")
End Select

You cannot use this syntax in C#. Instead, you must use the syntax from your first example.

Solution 5:

You can leave out the newline which gives you:

case 1: case 2: case 3:
   break;

but I consider that bad style.