Change Form window ownership : Form Frame Window : GUI Windows Form C# Source Code

    

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class ChildForm : Form
{
  public System.Windows.Forms.Label lblState;

  public ChildForm()
  {
    InitializeComponent();
  }
  private void InitializeComponent()
  {
    this.lblState = new System.Windows.Forms.Label();
    this.SuspendLayout();
    // 
    // lblState
    // 
    this.lblState.Location = new System.Drawing.Point(26, 24);
    this.lblState.Name = "lblState";
    this.lblState.Size = new System.Drawing.Size(184, 56);
    this.lblState.TabIndex = 2;
    // 
    // ChildForm
    // 
    this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
    this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
    this.ClientSize = new System.Drawing.Size(236, 104);
    this.Controls.Add(this.lblState);
    this.Font = new System.Drawing.Font("Tahoma", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
    this.Name = "ChildForm";
    this.Text = "ChildForm";
    this.ResumeLayout(false);

  }
  
}

public class ParentForm : Form{
  private System.Windows.Forms.Button cmdReleaseOwnership;
  private System.Windows.Forms.Button cmdAddOwnership;

  public ParentForm()
  {
    InitializeComponent();
    frmOwned.Show();

  }

  private ChildForm frmOwned = new ChildForm();


  private void cmdAddOwnership_Click(object sender, System.EventArgs e)
  {
    this.AddOwnedForm(frmOwned);
    frmOwned.lblState.Text = "Owned. Minimize me to see the difference.";
  }

  private void cmdReleaseOwnership_Click(object sender, System.EventArgs e)
  {
    this.RemoveOwnedForm(frmOwned);
    frmOwned.lblState.Text = "Not owned! Minimize me to see the difference.";
  }
  private void InitializeComponent()
  {
    this.cmdReleaseOwnership = new System.Windows.Forms.Button();
    this.cmdAddOwnership = new System.Windows.Forms.Button();
    this.SuspendLayout();
    // 
    // cmdReleaseOwnership
    // 
    this.cmdReleaseOwnership.FlatStyle = System.Windows.Forms.FlatStyle.System;
    this.cmdReleaseOwnership.Location = new System.Drawing.Point(150, 197);
    this.cmdReleaseOwnership.Name = "cmdReleaseOwnership";
    this.cmdReleaseOwnership.Size = new System.Drawing.Size(128, 32);
    this.cmdReleaseOwnership.TabIndex = 6;
    this.cmdReleaseOwnership.Text = "Remove Ownership";
    this.cmdReleaseOwnership.Click += new System.EventHandler(this.cmdReleaseOwnership_Click);
    // 
    // cmdAddOwnership
    // 
    this.cmdAddOwnership.FlatStyle = System.Windows.Forms.FlatStyle.System;
    this.cmdAddOwnership.Location = new System.Drawing.Point(14, 197);
    this.cmdAddOwnership.Name = "cmdAddOwnership";
    this.cmdAddOwnership.Size = new System.Drawing.Size(120, 32);
    this.cmdAddOwnership.TabIndex = 5;
    this.cmdAddOwnership.Text = "Set Ownership";
    this.cmdAddOwnership.Click += new System.EventHandler(this.cmdAddOwnership_Click);
    // 
    // ParentForm
    // 
    this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
    this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
    this.ClientSize = new System.Drawing.Size(292, 266);
    this.Controls.Add(this.cmdReleaseOwnership);
    this.Controls.Add(this.cmdAddOwnership);
    this.Font = new System.Drawing.Font("Tahoma", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
    this.Name = "ParentForm";
    this.Text = "Owner";
//    this.Load += new System.EventHandler(this.ParentForm_Load);
    this.ResumeLayout(false);

  }

  [STAThread]
  static void Main()
  {
    Application.EnableVisualStyles();
    Application.Run(new ParentForm());
  }

}