Question

How can I copy a Dictionary<string, string> to another new Dictionary<string, string> so that they are not the same object?

Answer 1

Assuming you mean you want them to be individual objects, and not references to the same object pass the source dictionary into the destination’s constructor:

Dictionary<string, string> d = new Dictionary<string, string>();
Dictionary<string, string> d2 = new Dictionary<string, string>(d);

"so that they are not the same object."

Ambiguity abound – if you do actually want them to be references to the same object:

Dictionary<string, string> d = new Dictionary<string, string>();
Dictionary<string, string> d2 = d;

(Changing either d or d2 after the above will affect both)