Trouble using the ref keyword. Very newbie question!
c#, ref
Solution
When you pass a reference type (in your case, your `UserInformation` class is a reference type) as a parameter, by default you are passing the pointer to the class by value, meaning the `GetPersonalDetails` would get its own copy of a pointer which points to the same instance of the `UserInformation` class.
Using the `ref` keyword in your example will pass the same pointer to the `UserInformation`instance to the method.
So in your case, if your intent is to simple modify the properties of `UserInformation`, the `ref` keyword in not needed, since you will be modifying the actual instance from `GetPersonalDetails` and `GetMachineDetails`. However, if your intent is to instantiate a new `UserInformation` object from inside those methods or set the instance to null, you would need to use the `ref` keyword.
Jon Skeet does a great job of explaining parameter passing in this article.
Problem
Here's my class: ``` public class UserInformation { public string Username { get; set; } public string ComputerName { get; set; } public string Workgroup { get; set; } public string OperatingSystem { get; set; } public string Processor { get; set; } public string RAM { get; set; } public string IPAddress { get; set; } public UserInformation GetUserInformation() { var CompleteInformation = new UserInformation(); GetPersonalDetails(ref CompleteInformation); GetMachineDetails(ref CompleteInformation); return CompleteInformation; } private void GetPersonalDetails(ref UserInformation CompleteInformation) { } private void GetMachineDetails(ref UserInformation CompleteInformation) { } } ``` I'm under the impression that the ref keyword tells the computer to use the same variable and not create a new one. Am I using it correctly? Do I have to use ref on both the calling code line and the actual method implementation?