as title said "does sending an instance from a class has same effect as send it by ref"
for example
FillStudentInformation(student); has the same effect of
FillStudentInformation(ref student); Does I expect that both instance will be changed by this call in same manner.
Note: FillStudentUnformation is a void method
The main difference is that if you do something like inside the method:
student = new Student(); In the second case, you will change the student object outside of the method too (not in the first case).
Using things like:
student.Name = 'John Doe'; will work the same for both.
However, you should try to avoid reference as much as you can because it can lead to more side effects and a lower testability.
You should not expect same behavior as both are different thing if I assume that Student is object of class(reference type). It also depend on that what you do inside method.
In First method
void Main() { Student student = new Student(); FillStudentUnformation(student); Console.WriteLine(student.Name); // Here you will not get name FillStudentUnformationRef(ref student); Console.WriteLine(student.Name); // you will see name you have set inside method. } vodi FillStudentUnformation(Student student) { //If here if you do student = new Student(); student.Name = "test"; // This will not reflect outside. } vodi FillStudentUnformationRef(ref Student student) { //If here if you do student = new Student(); student.Name = "test ref"; // This will not reflect outside. } So when we pass reference type to method it will pass copy of reference to that variable. So when you update that variable with new it will update that variable reference and not the actual one.
In second method it will pass actual reference so when you update it will affect the actual referene of object.
more on this : http://msdn.microsoft.com/en-IN/library/s6938f28.aspx
