Passing a struct by Reference

You can pass a struct by reference using the ref or out parameter modifiers.  Use ref when you want a method to read and write to the struct.  Use out for a struct that is meant to be an output parameter.
Assuming that you’ve defined the following struct:
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public struct MovieInfo
{
    public string Title;
    public int Year;
    public string Director;
}
You might pass an instance of MovieInfo by reference like this:
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public static void DisplayThenUpper(ref MovieInfo minfo)
{
    Console.WriteLine("{0} ({1}), {2}", minfo.Title, minfo.Year, minfo.Director);
 
    minfo.Title = minfo.Title.ToUpper();
    minfo.Director = minfo.Director.ToUpper();
}
After we call the method, the contents of the struct have been modified.
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MovieInfo minf = new MovieInfo();
minf.Title = "Citizen Kane";
minf.Year = 1941;
minf.Director = "Orson Welles";
 
Movie.DisplayThenUpper(ref minf);
 
Console.WriteLine("{0}, {1}", minf.Title, minf.Director);
Output after the program has finished:
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