[Solved] Show String Data in Message Box C#

Try this:

MessageBox.Show(String.Format("{0}, {1}, {2}:", city, zip, state));

This go replace {0} with the variable city, {1}with the variable zip and {3} with state.

String.Format converts the value of objects to strings based on the formats specified and inserts them into another string.

^{If you are new, read getting started with the String.Format method}

New in C# 6 is this:

MessageBox.Show($"{city}, {zip}, {state}");

^{Commented by @Lucas Trzesniewski}

Another opinion is use this:

MessageBox.Show(city + ", " + zip  + ", " + state);

Just past it all together.