.NET - I want to do this: Dim D as new Dictionary(of String, Array(OF MYOBJECT))

Question

I'd like to create a Dictionary that is indexed by Strings: Dictionary(of String, ...)

I'd like the Type after the comma to be an Array of MyObject's.

If all I do is the following:

Dim D as new Dictionary(of String, Array)

I feel like I'm missing out on some performance very time I access a member:

Dim Object1 as MyObject = MyDictionary("Key1")(4)

Doesn't it have to perform some type of lookup to figure out what type of object the array is holding every time I access it in this manner?

Answer 1

Using array, you will be invoking type casting when you retrieve it. How about this:

Dim D as new Dictionary(of String, List(of MyObject))

Answer 2

If the Value really needs to be an array of MyObject, you could do the following:

Dim D as new Dictionary(of String, MyObject())

Answer 3

Array isn’t what you want; rather, use the strongly typed array that you want to have:

Dim D as New Dictionary(Of String, MyObject())()

This works like a charm.