在C＃中的切换情况下分配枚举

Question

I need to change my Enum in switch case statement like below

var en; 
switch (RequestTypID.ToString())
            {
                case "15":
                    en = enum1;
                    break;
                case "16":
                    en = enum2;
                    break;
                case "14":
                    en = enum3;
                    break;
                case "13":
                    en = enum4;
                    break;
                default:
                    break;
            }

and then pas it to a foreach loop like this

foreach (var status in Enum.GetValues(typeof(en)))

i`m geeting an error that says en must be initialize ? what type should i declare for en variable ? what type should i declare for status variable ?

alright i`ve added this line to the code and one problem is solved;

var en = typeof(enum1);

but now it say it cant find en reference in my for each loop ?

i also change my switch case to something like this

switch (RequestTypID.ToString())
            {
                case "15":
                    en = typeof(enum1);
                    break; 
                    ....

Answer 1

i`m geeting an error that says en must be initialize ?

This is reasonable, because this var en; is not correct. When we want to declare something implicitly, we have to assign a value to it, when we declare it, in order the compiler infer it's type.

For instance, var n = 4; . The 4 can be stored to a variable of type int . Hence the compiler, when see this declaration understands that the tyoe of n int.

Answer 2

You can't create an variable with var ( var isn't a type) and not assign a value to it. Var means that compiler will evaluate it's type seeing it's value, but here you don't have a value of the variable.So you need to assign a value to your variable en .Assign a value which type is enum1, enum2, enum3, enum4 ..

Answer 3

You have to have another variable to the right side of the var statement so the compile know what to expect.

You should do the following:

var en = YourEnum.Option1;

or

YourEnum en;

Answer 4

Enum.GetValues require a Type as parameter. So simply declare you en as Type .

Type en = null;

you cannot declare it as var without initializing it: compiler need to know what is the real type you want to use.

also, you have to change in your switch:

en = typeof(SomeEnum);