如何将两个不同类型的列表合并为一个包含两种类型的新类型列表？

Question

I want to combine/merge/join/whatever a list of enum s, so that each item in the unified list will have two fields - the name of the enum item ( string Name ), and its value ( TokensEnum Token ):

var tokens = Enum.GetValues(typeof (TokensEnum));
var names = Enum.GetNames(typeof (TokensEnum));

var combined = InTheDarknessBindThem(tokens,names);

foreach(var c in combined)
    MessageBox.Show(string.Format(
        "Token \"{0}\" value is {1}", c.Name, (int)c.Token));

How to write the body of the following method (preferably LINQ-wise)?

InTheDarknessBindThem(IEnumerable<TokensEnum> tokens, IEnumerable<string> names) {
    /*
        ...
    */
}

Answer 1

If both lists are in order, you can use the Zip extension method:

tokens.Cast<TokensEnum>().Zip(names, (t, n) => Tuple.Create(t, n));

This will return an IEnumerable<Tuple<TokensEnum, string>> .

But as Jon Skeet suggests , in this case, it would probably be easier to do something like this:

Enum.GetValues(typeof(TokensEnum))
    .Cast<TokensEnum>()
    .Select(t => Tuple.Create(t, t.ToString()));

This will return the same result as above, but it will do it in a single step.

Since you mentioned in your comments that you'd like to have a Dictionary<string, TokensEnum> , you can use something like this to construct it:

Dictionary<string, TokensEnum> myDictionary = 
    Enum.GetValues(typeof(TokensEnum))
        .Cast<TokensEnum>()
        .ToDictionary(t => t.ToString());

Answer 2

Why not a dictionary?

var dict = Enum.GetValues(typeof (TokensEnum))
               .Cast<TokensEnum>()
               .ToDictionary(x => x, x => x.ToString());
foreach (var kvp in dict)
{
    Console.WriteLine("Value: {0}, Name: {1}",kvp.Key,kvp.Value);
}

The printout is a bit moot since ToString() is called on value.

I think using enum as key in a dictionary cases boxing.