What is the most appropriate way to compare a string to a stringable object by value?

Question

With this:

if (args.Parameter == "ContactIntermediaryPage")

...in a NavigatedTo() event handler, Resharper tells me: "Possible unintended reference comparison; to get a value comparison, cast the left hand side to type 'string'"

So should I change it to one of the following, and, if so, which one:

if ((string)args.Parameter == "ContactIntermediaryPage")

if (args.Parameter.ToString() == "ContactIntermediaryPage")

if (args.Parameter.Equals("ContactIntermediaryPage"))

Answer 1

I would choose third one, making it also case insensitive (if this is suitable in your case)

if (args.Parameter.ToString().Equals(
               "ContactIntermediaryPage", 
                StringComparsion.InvariantCultureIgnoreCase))

In other words, if you're comparing to a string make left part of equation a string, to make clear to a compiler and to a reader of your code, what you're going to do on that line.

Answer 2

the first one if args.Parameter is always a string. It saves an extra call.

otherwise the second one if, and only if, all possible strings are within your code. If so, I would define the strings as constants and reference them in one place if possible.

If neither of the above are true, then go for Tigran's answer.