Constant value cannot be converted to a 'bool' using a switch statement C#

Question

When I try to evaluate the SelectedIndex of a CheckBoxList and at bool. I receive a error on the case in my switch statement in C#. The error is Constant value '0' cannot be converted to a 'bool'. Is there a way that I can evaluate both with in a switch statement? I know I can use a if statement, but I would rather use a switch statement if I could.

Here is my code:

switch ((CBL_PO.SelectedIndex == 0) && (boolIsNotValid == true))
            {
                case 0: case true:
                    //Do Something
                    break;
            }

What is the need for a switch statement? `(CBL_PO.SelectedIndex == 0) && (boolIsNotValid == true)` can only return true of false — Mike Norgate, Aug 05 '14 at 12:51
@PatrickHofman Yes there will be a value of 0, someone may check the first box in the list — nate, Aug 05 '14 at 12:58
I think you are trying to combine two statements in one. You can't. — Patrick Hofman, Aug 05 '14 at 12:59
@PatrickHofman http://stackoverflow.com/questions/68578/multiple-cases-in-switch — nate, Aug 05 '14 at 13:00
That answer states in it's first line: "There is no syntax in C++ nor C# for the second method you mentioned." — Patrick Hofman, Aug 05 '14 at 13:01
I do. It has multiple values, but one variable to check against. — Patrick Hofman, Aug 05 '14 at 13:03
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/58704/discussion-between-nate-and-patrick-hofman). — nate, Aug 05 '14 at 13:05

Patrick Hofman · Accepted Answer · 2014-08-05T13:01:16.833

Since the only values in the switch can be true or false, drop the case 0.

Alternatively, you could better use an if:

if (CBL_PO.SelectedIndex == 0 && boolIsNotValid)
{ }
else
{ }

Since I think you might be trying to do a check on both values in the switch: not possible. This is your best option:

switch (CBL_PO.SelectedIndex)
{
    case 0:
    {
        if (boolIsNotValid)
        { }
        else
        { }

        break;
    }
}

score 1 · Answer 2 · answered Aug 05 '14 at 12:52

1

A switch statement can be thought of as a replacement for a stack of if/else statements. If you are doing a single comparison then use a simple if statement; switch is overkill.

if (CBL_PO.SelectedIndex == 0 && boolIsNotValid)
{
  // Do something
}

answered Aug 05 '14 at 12:52

Rob Epstein

1,450
9
11

score 0 · Answer 3 · answered Aug 05 '14 at 12:52

0

If you really want to use a switch statement, then you want:

switch ((CBL_PO.SelectedIndex == 0) && (boolIsNotValid == true))
    {
        case true:
           //Do Something
           break;
        case false:
           //Do Something else
           break;
    }

answered Aug 05 '14 at 12:52

Mark Nash

184
10

So I can evaluate the SelectedIndex == 0 as the case being false? Never thought of that. I am going to try that now. – nate Aug 05 '14 at 13:02
I can't change the case to false, if I do, I can't evaluate with checkbox will be checked in the list. – nate Aug 05 '14 at 13:10

Constant value cannot be converted to a 'bool' using a switch statement C#

3 Answers3