Count values in Dictionary using LINQ and LINQ extensions

Question

I have a dictionary that looks something like this:

Dictionary<String, List<String>>

test1 : 1,3,4,5
test2 : 2,3,6,7
test3 : 2,8

How can I get a count of all the values using LINQ and LINQ extensions?

Solution 1

Let's say you have:

Dictionary<String, List<String>> dict = ...

If you want the number of lists, it's as simple as:

int result = dict.Count;

If you want the total count of all the strings in all the lists:

int result = dict.Values.Sum(list => list.Count);

If you want the count of all the distinct strings in all the lists:

int result = dict.Values
                 .SelectMany(list => list)
                 .Distinct()
                 .Count();

Solution 2

How about

yourdictionary.Values.Sum(l => l.Count);

Comments

[pengibot]

Thanks, Yeah it was the total count of all the strings in all the lists I was after. Very concise and well explained answer. I am new to Linq so am still getting use to how to do things.

[pengibot]

I was also after the way to do it using from mylist in dict where logic too, which would be useful to see how to do the same. thanks