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Cast Int to Generic Enum in C#

Similar to Cast int to enum in C# but my enum is a Generic Type parameter. What is the best way to handle this?

Example:

private T ConvertEnum<T>(int i) where T : struct, IConvertible
{
    return (T)i;
}

Generates compiler error Cannot convert type 'int' to 'T'

Full code is as follows, where value can contain the int, or null.

private int? TryParseInt(string value)
{
    var i = 0;
    if (!int.TryParse(value, out i))
    {
        return null;
    }
    return i;
}

private T? TryParseEnum<T>(string value) where T : struct, IConvertible
{
    var i = TryParseInt(value);
    if (!i.HasValue)
    {
        return null;
    }

    return (T)i.Value;
}
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0 votes
by (71.8m points)

The simplest way I have found is to force the compiler's hand by adding a cast to object.

return (T)(object)i.Value;

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