C# 4 and .NET 4

1120 ❘ ChaPTer 39 windOws fOrms
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
///
/// Required method for Designer support—do not modify
/// the contents of this method with the code editor.
///
private void InitializeComponent()
{
this.components =
new System.ComponentModel.Container();
this.AutoScaleMode =
System.Windows.Forms.AutoScaleMode.Font;
this.Text = "Form1";
}
#endregion
}
}
code snippet Form1.Designer.cs
The Designer file of a form should rarely be edited directly. The only exception is if there is any special
processing that needs to take place in the Dispose method. The InitializeComponent method is discussed
later in this chapter.
Looking at the code as a whole for this sample application, you can see it is much longer than the simple
command-line example. There are several using statements at the start of the class; most are not necessary
for this example. There is no penalty for keeping them there. The class Form1 is derived from System
.Windows.Forms.Form just like the earlier Notepad example, but things start to get different at this point.
First, there is this line in the Form1.Designer file:
private System.ComponentModel.IContainer components = null;
In the example, this line of code doesn’t really do anything. When you add a component to a form, you can
also add it to the components object, which is a container. The reason for adding to this container has to do
with disposing of the form. The form class supports the IDisposable interface because it is implemented in
the Component class. When a component is added to the components object, this container will make sure
that the components are tracked properly and disposed of when the form is disposed of. You can see this if
you look at the Dispose method in the code:
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
Here you can see that when the Dispose method is called, the Dispose method of the components object is
also called, and because the component object contains the other components, they are also disposed of.
The constructor of the Form1 class, which is in the Form1.cs file, looks like this:
public Form1()
{
InitializeComponent();
}
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