Essential Books

Changing values elsewhere

suggest change 
public static void Main(string[] args)
{
  var studentList = new List<Student>();
  studentList.Add(new Student("Scott", "Nuke"));
  studentList.Add(new Student("Vincent", "King"));
  studentList.Add(new Student("Craig", "Bertt"));

  // make a separate list to print out later
  var printingList = studentList; // this is a new list object, but holding the same student objects inside it

  // oops, we've noticed typos in the names, so we fix those
  studentList[0].LastName = "Duke";
  studentList[1].LastName = "Kong";
  studentList[2].LastName = "Brett";

  // okay, we now print the list
  PrintPrintingList(printingList);
}

private static void PrintPrintingList(List<Student> students)
{
  foreach (Student student in students)
  {
      Console.WriteLine(string.Format("{0} {1}", student.FirstName, student.LastName));
  }
}

You’ll notice that even though the printingList list was made before the corrections to student names after the typos, the PrintPrintingList method still prints out the corrected names: 

Scott Duke
Vincent Kong
Craig Brett

This is because both lists hold a list of references to the same students. SO changing the underlying student object propogates to usages by either list.

Here’s what the student class would look like. 

public class Student
{
    public string FirstName { get; set; }
    public string LastName { get; set; }

    public Student(string firstName, string lastName)
    {
        this.FirstName = firstName;
        this.LastName = lastName;
    }
}
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Value type vs Reference type:
* Value type vs Reference type
* Passing by reference using ref keyword.
* Changing values elsewhere
* Passing by reference
* Difference with method parameters ref and out
* ref vs out parameters
* Assignment
Table Of Contents
0 Getting Started With C#
1 Literals
2 Operators
3 Conditional Statements
4 Equality Operator
5 Equals and GetHashCode
6 Null-Coalescing Operator
7 Null-Conditional Operators
8 nameof Operator
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30 Value type vs Reference type
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118 Task Parallel Library TPL Dataflow Constructs
119 Functional Programming
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125 Accessing Databases
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130 Structural Design Patterns
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134 System.Management.Automation
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137 Simulating C Unions with C# Structs
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139 AsseblyInfo.cs examples
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142 ObservableCollection
143 Hash Functions
144 Generating Random Numbers
145 Cryptography
146 Unsafe Code in .NET
147 C# Script
148 Runtime Compile
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150 .NET Compiler Platform Roslyn
151 Creating Own MessageBox in Windows Form Application
152 Including Font Resources
153 Garbage Collector
154 Windows Communication Foundation
155 Contributors