title: Error with Tuple in C# 2008
body: <p>I have made a program in C# 2010 and my code contains a Tuple, but when I put my program into C# 2008 it does not recognise it, and comes up with the error of: </p>
  
  <p><code>"The type of namespace name 'Tuple' could not be found"</code></p>
  
  <p>So I don't know how to make this work, this is the line of code in which the error occurs:</p>
  
  <pre><code>private List&lt;Tuple&lt;Point, Point&gt;&gt; lines = new List&lt;Tuple&lt;Point, Point&gt;&gt;();
  </code></pre>
  
  <p>Please help.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Basically this is my code at the moment which doesn't compile due to the error:</p>
  
  <pre><code>public partial class Form1 : Form
  {
      private bool isMoving = false;
      private Point mouseDownPosition = Point.Empty;
      private Point mouseMovePosition = Point.Empty;
      private List&lt;Tuple&lt;Point, Point&gt;&gt; lines = new List&lt;Tuple&lt;Point, Point&gt;&gt;();
      public Form1()
      {
          InitializeComponent();
      }
  
      private void pictureBox1_Paint(object sender, PaintEventArgs e)
      {
          var g = e.Graphics;
          if (isMoving)
          {
              g.Clear(pictureBox1.BackColor);
              g.DrawLine(Pens.Black, mouseDownPosition, mouseMovePosition);
              foreach (var line in lines)
              {
                  g.DrawLine(Pens.Black, line.Item1, line.Item2);
              }
          }
      }
  
      private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
      {
          isMoving = true;
          mouseDownPosition = e.Location;
      }
  
      private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
      {
          if (isMoving)
          {
              mouseMovePosition = e.Location;
              pictureBox1.Invalidate();
          }
      }
  
      private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
      {
          if (isMoving)
          {
              lines.Add(Tuple.Create(mouseDownPosition, mouseMovePosition));
          }
          isMoving = false;
      }
  }
  </code></pre>
  
  <p>So I need a way of changing or making the Tuple work in VS C# 2008 as well as 2010,</p>
  
  <p>Thanks</p>