Opening a form


	frmConfiguration ConfigForm = new frmConfiguration();
	ConfigForm.PassedValue1 = "This is a string I'm passing";

	//TO OPEN AS A DIALOG FORM:
	ConfigForm.ShowDialog();
	//or
	if (ConfigForm.ShowDialog() == System.Windows.Forms.DialogResult.OK)
	else if (ConfigForm.DialogResult == System.Windows.Forms.DialogResult.Cancel)

	//TO OPEN NOT AS A DIALOG FORM:
	ConfigForm.Show();

Closing a form


	Close();
	//or
	this.Close();

Closing a form from the Form Load Event

You can't use this.Close as the form has not yet finished loading so if you do you'll cause fatal error. Instead use this:


	this.BeginInvoke(new MethodInvoker(this, System.Windows.Forms.Form.Close));

Dynamically updating Form Properties

Use this instead of the forms name:

	this.Text = "A New Title For This Form";

To Disable A Form


	//This form
	this.Enabled = false;
	//Another form
	frmMyForm.Enabled = false;

Why Is A Form Closing?

You can use things like this (see the CloseReason members):

if (e.CloseReason == System.Windows.Forms.CloseReason.UserClosing)

Supressing Display Update Of A Form

You can't stop a form being painted, but you can do this:


	this.SuspendLayout();
	MyControlName1.SuspendLayout();
	MyControlName2.SuspendLayout();
	...
	MyControlName1.ResumeLayout();
	MyControlName2.ResumeLayout();
	this.ResumeLayout();

You can also make specific controls invisible

Default Accept and Cancel Buttons

Set in the forms AcceptButton and CancelButton properties.
Set Dialog result for each button

Returning a Dialog Result

You can assign a dialog result value to buttons on the form in their properties.

Stopping A Form / Application From Closing

Handle the form's 'Closing' event and set 'e.Cancel' to 'True' if you want to prevent the form from closing.
e.Cancel = true;
If your going to present a message box, such as a 'do you want to save' then you need to do the cancel first to stop the ap closing while waiting for the user input. Then afterwards do the close.

 

 

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