How to TryParse for Enum value?

Question

I want to write a function which can validate a given value (passed as a string) against possible values of an enum. In the case of a match, it should return th

Answer 1

In the end you have to implement this around Enum.GetNames:

public bool TryParseEnum(string str, bool caseSensitive, out T value) where T : struct {
    // Can't make this a type constraint...
    if (!typeof(T).IsEnum) {
        throw new ArgumentException("Type parameter must be an enum");
    }
    var names = Enum.GetNames(typeof(T));
    value = (Enum.GetValues(typeof(T)) as T[])[0];  // For want of a better default
    foreach (var name in names) {
        if (String.Equals(name, str, caseSensitive ? StringComparison.Ordinal : StringComparison.OrdinalIgnoreCase)) {
            value = (T)Enum.Parse(typeof(T), name);
            return true;
        }
    }
    return false;
}

Additional notes:

• Enum.TryParse is included in .NET 4. See here http://msdn.microsoft.com/library/dd991876(VS.100).aspx
• Another approach would be to directly wrap Enum.Parse catching the exception thrown when it fails. This could be faster when a match is found, but will likely to slower if not. Depending on the data you are processing this may or may not be a net improvement.

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EDIT: Just seen a better implementation on this, which caches the necessary information: http://damieng.com/blog/2010/10/17/enums-better-syntax-improved-performance-and-tryparse-in-net-3-5