Convert dictionary values into array

What is the most efficient way of turning the list of values of a dictionary into an array?

For example, if I have a Dictionary where Key is String and Value is Foo, I want to get Foo[]

I am using VS 2005, C# 2.0

5 Answers

// dict is Dictionary<string, Foo> Foo[] foos = new Foo[dict.Count]; dict.Values.CopyTo(foos, 0); // or in C# 3.0: var foos = dict.Values.ToArray(); 

Store it in a list. It is easier;

List<Foo> arr = new List<Foo>(dict.Values); 

Of course if you specifically want it in an array;

Foo[] arr = (new List<Foo>(dict.Values)).ToArray(); 

There is a ToArray() function on Values:

Foo[] arr = new Foo[dict.Count]; dict.Values.CopyTo(arr, 0); 

But I don't think its efficient (I haven't really tried, but I guess it copies all these values to the array). Do you really need an Array? If not, I would try to pass IEnumerable:

IEnumerable<Foo> foos = dict.Values; 

If you would like to use linq, so you can try following:

Dictionary<string, object> dict = new Dictionary<string, object>(); var arr = dict.Select(z => z.Value).ToArray(); 

I don't know which one is faster or better. Both work for me.

These days, once you have LINQ available, you can convert the dictionary keys and their values to a single string.

You can use the following code:

// convert the dictionary to an array of strings string[] strArray = dict.Select(x => ("Key: " + x.Key + ", Value: " + x.Value)).ToArray(); // convert a string array to a single string string result = String.Join(", ", strArray);