Question

I have two string lists which have same size.
I want to create a dictionary, the key is from listA, the value is from listB.

What is the fast way?

I used the code:

        List<string> ListA;
        List<string> ListB;
        Dictionary<string,string> dict = new Dictionary<string,string>();
        for(int i=0;i<ListA.Count;i++)
        {
              dict[key] = listA[i];
              dict[value]= listB[i];
        }

I don’t like this way, can I use ToDictionary method?

Answer 1

Starting with .NET 4.0, you can do it using LINQ’s Zip method, like this:

var res = ListA.Zip(ListB, (a,b) => new {a, b})
               .ToDictionary(p=>p.a, p=>p.b);

[Zip] method merges each element of the first sequence with an element that has the same index in the second sequence.