Purpose of the IDictionary interface

Question

What the IDictionary interface needs. How can I initialize the IDictionary interface. After all, this is just an interface. The following code snippet is from msdn. I could not understand this.

IDictionary<string, string> openWith = new Dictionary<string, string>();

Answer 1

It defines the important functions that a dictionary should implement.

A line from MSDN means that you are creating an openWith object that implements the functions (methods) defined in the IDictionary interface .

When you use a dictionary to declare a variable:

Dictionary<string,string> openWith=.....;

You are communicating with a particular type of object. But when you use

IDictionary<string,string> openWith=....;

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Answer 2

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Answer 3

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Answer 4

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Answer 5

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