Hi,
I'm pretty sure I must do something terrible wrong, but it surely does look
like some sort of leak in the GC. (.NET 1.1)
What I did:
created a form, dropped a ContextMenu on it, connected it to the form.
Then I added an emtpy MenuItem to the Menu. No events for the MenuItem,
nothing else.
If I create the Form
f = new Form2();
f.Show();
and free it afterwards
f.Close()
f.Dispose()
f = null;
everything is fine.
BUT:
If I do a right-click on the created form, so that the ContextMenu pops up,
the Form, ContextMenu and the MenuItem wont be collected by the GC.
I went through this by using a Memory-Profiler http://memprofiler.com/.
Can somebody explain to me, whats happening?
Regards,
Michael Sander
// SOURCE-CODE FOR THE EXAMPLE
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace LeakTest
{
/// <summary>
/// Summary description for Form1.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.Container components = null;
public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(40, 44);
this.button1.Name = "button1";
this.button1.TabIndex = 0;
this.button1.Text = "create form";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(40, 88);
this.button2.Name = "button2";
this.button2.TabIndex = 1;
this.button2.Text = "destroy form";
this.button2.Click += new System.EventHandler(this.button2_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(164, 169);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);
}
#endregion
/// <summary>
/// Summary description for Form2.
/// </summary>
public class Form2 : System.Windows.Forms.Form
{
private System.Windows.Forms.ContextMenu contextMenu1;
private System.Windows.Forms.MenuItem menuItem1;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.Container components = null;
public Form2()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if(components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.contextMenu1 = new System.Windows.Forms.ContextMenu();
this.menuItem1 = new System.Windows.Forms.MenuItem();
//
// contextMenu1
//
this.contextMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[]
{
this.menuItem1});
//
// menuItem1
//
this.menuItem1.Index = 0;
this.menuItem1.Text = "nothing";
//
// Form2
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 273);
this.ContextMenu = this.contextMenu1;
this.Name = "Form2";
this.Text = "Form2";
}
#endregion
}
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
Form2 f;
private void button1_Click(object sender, System.EventArgs e)
{
f = new Form2();
f.Show();
}
private void button2_Click(object sender, System.EventArgs e)
{
f.Close();
f.Dispose();
f = null;
}
}
}
