Using a switch statement to set the value of one particular variable only?

Question

Is there a way to use a switch statement to set the value of one particular variable used throughout the cases? At the moment if value is 1, I want variable to be 1, and if value is 2, I want variable to be 2. I am actually doing it simply by:

Int variable = value;

..however, for future reference where an example is more complex, I wondered if there is a way. (currently getting a variable is already defined error).

  switch (value)
        {
            case 0:
                int Variable = 0;
                break;
            case 1:
                int Variable = 1;
                break;
            case 2:
                int Variable = 2;
                break;
            case 3:
                int Variable = 3;
                break;
            case 4:
                int Variable = 4;
                break;
        }

All the cases within a `switch` are all in the same scope. Just put your variable declaration outside of it and assign to it normally. — Jeff Mercado, Jun 26 '12 at 00:43
Ahh, so obvious now you point it out, I was declaring the variable over and over, thanks alot! — user1166981, Jun 26 '12 at 00:44
He means why use a switch statement to assign the same value that value contains. Just keep using int Variable = value unless you know that you will eventually assign a different result to Variable. Oh, and read a bit on naming conventions. — JohnP, Jun 26 '12 at 00:49
No I meant I wanted to learn how to do it where for example it is more complex such as if I have a string in one variable and want to set another variable to a specific int based on the text, if you know what I mean..(for future reference) — user1166981, Jun 26 '12 at 00:51

score 5 · Answer 1 · edited May 23 '17 at 11:58

5

How about a hashtable or dictionary. It's troublesome but quite readable i guess.

Idea taken from here.

Dictionary<string, int> numbers = new Dictionary<string, int>(){
    {"zero", 0},
    {"one", 1},
    {"two", 2},
    {"three", 3},
    {"four", 4},
    {"five", 5},
    {"size", 6}
};

int Variable = numbers[value];

edited May 23 '17 at 11:58

Community

1
1

answered Jun 26 '12 at 01:14

viclim

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score 2 · Accepted Answer · edited Jun 26 '12 at 00:58

2

If you declare your variable outside the swtich, you won't get the "variable already defined" error. This is happening because everything inside the switch is in the same scope.

Example:

int Variable = -1;

switch (value)
{
        case 0:
            Variable = 0;
            break;
        case 1:
            Variable = 1;
            break;
        case 2:
            Variable = 2;
            break;
        case 3:
            Variable = 3;
            break;
        case 4:
            Variable = 4;
            break;
}

edited Jun 26 '12 at 00:58

Blorgbeard

101,031
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answered Jun 26 '12 at 00:45

Icarus

63,293
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An `else` clause would be a worthwhile addition to handle any unexpected values. A possible alternative is to use a nullable type, e.g. `int? Variable;`. – HABO Jun 26 '12 at 02:22

Using a switch statement to set the value of one particular variable only?

2 Answers2

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