How to use a switch statement with Guid?

问题:

In the following C# code, cboRole returns a Guid.

I'm then trying to use it in a switch statement to do some actions.

cboRole can return only 4 different Guid so I think a switch is a good option for me.

The thing is that all the case are ignored and I always get the default action. When I debug I clearly see that cboRole return a value like in the following printscreen.

What is the correct way to "compare" Guids in a C# switch statement

Code:

if (!cboRole.IsNull)
{
    switch (cboRole.EditValue.ToStringEx())
        {
            case "532E8EED-9E72-42E0-871E-36470C1AE327":
                param1 = "4E08BA7C-E81F-40AE-92F0-DF33A98DD0BB";
                MessageBox.Show("It's working");
                break;
            case "FA7637E9-A9E4-4D57-A59B-80615424D27F":
                param1 = "E540C382-F22C-4FE2-9068-1E10AA8DD076";
                break;
            case "2734CCD9-93E6-4A86-8B83-5EA9E62FA921":
                param1 = "8A54F8D5-5B74-4B3F-A29A-D423AA8DD02E";
                break;
            default:
                MessageBox.Show("Not Working");
                break;
        }

回答1:

Your switch statements are in upper-case while your ToStringEx() returns the Guid in lower-case.

You can use

switch (cboRole.EditValue.ToStringEx().ToUpper())

or modify your case statements.

回答2:

with c#7 you can now use switch with Pattern Matching for this purpose.

switch (cboRole)
{
    case var r when (r == new Guid("532E8EED-9E72-42E0-871E-36470C1AE327")):
        param1 = "4E08BA7C-E81F-40AE-92F0-DF33A98DD0BB";
        MessageBox.Show("It's working");
        break;
    case var r when (r == new Guid("FA7637E9-A9E4-4D57-A59B-80615424D27F")):
        param1 = "E540C382-F22C-4FE2-9068-1E10AA8DD076";
        break;
    case var r when (r == new Guid("2734CCD9-93E6-4A86-8B83-5EA9E62FA921")):
        param1 = "8A54F8D5-5B74-4B3F-A29A-D423AA8DD02E";
        break;
    default:
        MessageBox.Show("Not Working");
        break;
}

This also works if you have defined static readonly new Guid"..") variables.