KeyNotFoundException in filled dictionary

Question

I am trying to modify value in dictionary, but the compiler throws KeyNotFoundException. I\'m sure, I declared that key in dictionary, because I am calling

Answer 1

Yes. You have not overridden GetHashCode.

Answer 2

Dictionary is using the GetHashCode and Equals for key comparisons, so implementing the IComparable interface is not enough. Have a look at this answer, that's exactly what you need.