“the given key was not present in the dictionary” error when using a self-defined class as key

Question

I\'ve got code like this:

if (CounterForEachRelatedTagDict.Select(x => x.Key).Contains(tag.Key))
   CounterForEachRelatedTagDict[tag.Key] += tag.Value;
         


        

Answer 1

First:You can use the ContainsKey method instead of that Linq Query.

Second: You must override the GetHashCode and Equals for MyType. that's the way that Dictionary look up and compare the keys.

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