Elegant way to go from list of objects to dictionary with two of the properties

Question

i seem to write this code over and over again and wanted to see if there was a better way of doing it more generically.

I start out with a list of Foo objects

Foo[] foos = GenerateFoos(); 

I think want to create a dictionary where the key and value are both properties of Foo

for example:

Dictionary<string, string> fooDict = new Dictionary<string, string>(): foreach (Foo foo in foos) {     fooDict[foo.Name] = foo.StreetAddress; } 

is there anyway of writing this code generically as it seems like a basic template where there is an array of objects, a key property a value property and a dictionary.

Any suggestions?

I am using VS 2005 (C#, 2.0)

Answer 1

With LINQ:

var fooDict = foos.ToDictionary(x=>x.Name,x=>x.StreetAddress); 

(and yes, fooDict is Dictionary<string, string>)

---

edit to show the pain in VS2005:

Dictionary<string, string> fooDict =     Program.ToDictionary<Foo, string, string>(foos,         delegate(Foo foo) { return foo.Name; },         delegate(Foo foo) { return foo.StreetAddress; }); 

where you have (in Program):

public static Dictionary<TKey, TValue> ToDictionary<TSource, TKey, TValue>(     IEnumerable<TSource> items,     Converter<TSource, TKey> keySelector,     Converter<TSource, TValue> valueSelector) {     Dictionary<TKey, TValue> result = new Dictionary<TKey, TValue>();     foreach (TSource item in items)     {         result.Add(keySelector(item), valueSelector(item));     }     return result; } 

Answer 2

If you are using framework 3.5, you can use the ToDictionary extension:

Dictionary<string, string> fooDict = foos.ToDictionary(f => f.Name, f => f.StreetAddress); 

For framework 2.0, the code is pretty much as simple as it can be.

You can improve the performance a bit by specifying the capacity for the dictionary when you create it, so that it doesn't have to do any reallocations while you fill it:

Dictionary<string, string> fooDict = new Dictionary<string, string>(foos.Count):