Using an enum and a switch statement c#

Question

I am using an enum as my options for a switch statement and it works. The problem is if the user enter a non valid option the program crashes. What should I add so that the default is used?

my enum class

    public enum Options : byte
    {
        Display = 1,
        Add,
        Toggle,
        Max,
        Mean,
        Medium,
        Exit
    }

in main my switch statement

    string volString = Console.ReadLine();
    Options options = (Options)Enum.Parse(typeof(Options), volString);
    // this is the line that is giving me the runtime error. Since other options are not found

in the enum the program crashes.

                switch (options)
                {
                    case Options.Display: //dispaly regular time

                    case Options.Toggle://toggle 

                    default:
                        Console.WriteLine("entry blah blah");
                        break;

Answer 1

Instead of Enum.Parse use Enum.TryParse ... this will return a boolean to say if the text can be converted into your enum. If it's true run your switch otherwise inform the user that they entered an invalid string.

Answer 2

Use Enum.TryParse instead:

Options options;

if(!Enum.TryParse(volString, out options)) {
    // It wasn't valid input.
}

Answer 3

How about:

Options value;
if(!Enum.TryParse(volString, out value)) // note implicit <Options>
    value = Options.SomeDefaultValue;

Answer 4

查看Enum.TryParse（...），您可以使用它来检查无效的字符串。