Why is my format giving me an error when I try to format an enum to a string?

Question

I have the following enum:

public enum EReferenceKey {
        Accounts             = 1,
        Emails                = 3,
        Phones               = 4
}

When my enum variable pk is Accounts and I try to convert this to "01" using

var a = pk.ToString("00");

it gives me the following exception:

Format String can be only "G", "g", "X", "x", "F", "f", "D" or "d"

Can someone explain what I am doing wrong?

Answer 1

You need to cast it to int before attempting that format string. Enum has its own ToString implementation, as such your int format string is not correct.

var a = ((int)pk).ToString("00");