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Disable Parent Control of a button in windows Forms

so what i want to do is, on Event ButtonClick disable parent Control of this button.
In my Form i have several Panel's in which those button actually are.
I am using following code:
private void button1_Click(object sender, EventArgs e)
{
Control control = button1.Parent;
control.Enabled = false;
}
This xode is working fine, but I wanted to use this.Parent instead of button1.Parent, so that each button would be able to disable its own parent Panel(in this case will disabled Panel of button1).
When i am using this.Parent I get a System.NullReferenceException.
Knows some one why i am getting this error ?

this is your current class you want to use the sender and cast it to Control than get it's parent something like this
private void button1_Click(object sender, EventArgs e)
{
var uc = sender as Control;
uc.Parent.Enabled = false;
}

this represents the Window, which has no Parent.
You can do the following:
private void button_Click(object sender, EventArgs e){
Control control = ((Button) sender).Parent;
control.Enabled = false;
}
Button[] buttons = {button, button2....};
foreach (Button button in buttons)
button.Click += button_Click;
Alternatively, you can create a class inheriting from Button. You can then add a Click event handler that disables it's parent control. You can then use this button instead of the default one.

Preserve control's visibility on condition

This is probably an easy one for some of you.
I have a TextBox and a ListBox. ListBox provides options for the TextBox and copies selected item's text to TextBox on DoubleClick event. ListBox becomes visible only when TextBox fires Enter event. I do not want to discuss my reasons for selecting this control combination.
I want ListBox to disappear when any other control within the Form gets focus. So I capture Leave event of TextBox and call ListBox.Visible = fale The problem is that TextBox will also loose focus when I click on ListBox to select provided option thus preventing me from selecting that option.
What event combination should I use to preserve ListBox to select option but hide it whenever other controls get focus?

In the Leave method, you can check to see if the ListBox is the focused control or not before changing its Visibility:
private void myTextBox_Leave(object sender, EventArgs e)
{
if (!myListBox.Focused)
{
myListBox.Visible = false;
}
}

This example will provide you with the desired outcome:
public Form1()
{
InitializeComponent();
textBox1.LostFocus += new EventHandler(textBox1_LostFocus);
textBox1.GotFocus += new EventHandler(textBox1_GotFocus);
}
void textBox1_GotFocus(object sender, EventArgs e)
{
listBox1.Visible = true;
}
void textBox1_LostFocus(object sender, EventArgs e)
{
if(!listBox1.Focused)
listBox1.Visible = false;
}
private void listBox1_MouseDoubleClick(object sender, MouseEventArgs e)
{
textBox1.Text = listBox1.SelectedItem.ToString();
}
private void Form1_Shown(object sender, EventArgs e)
{
//if your textbox as focus when the form shows
//this is the place to switch focus to another control
listBox1.Visible = false;
}

Put focus back on previously focused control on a button click event C# winforms

I have made a custom Number Keypad control that I want to place in my winform application. All of the buttons have an OnClick event to send a value to the focused textbox in my form where I have placed my custom control. Like this:
private void btnNum1_Click(object sender, EventArgs e)
{
if (focusedCtrl != null && focusedCtrl is TextBox)
{
focusedCtrl.Focus();
SendKeys.Send("1");
}
}
focusedCtrl is supposed to be set on the MouseDown event of the button like this:
private void btnNum1_MouseDown(object sender, EventArgs e)
{
focusedCtrl = this.ActiveControl;
}
where this.ActiveControl represents the active control on the form.
My problem is that the button always receives the focus before the event detects what the focused control was previously. How can I detect which control had the focus before the button got the focus? Is there another event I should be using? Thanks in advance!
EDIT: Also, I would rather not use the GotFocus event on each textbox in the form to set focusedCtrl since that can be tedious and because I would like to have all the coding of my custom control be in the control itself and not on the form where it is placed. (I will do this, though, if there is no other practical way to do what I am asking)

Your requirement is fairly unwise, you'll want some kind of guarantee that your button isn't going to poke text into inappropriate places. You really do need to have the form co-operate, only it knows what places are appropriate.
But it is not impossible, you can sniff at input events before they are dispatched to the control with the focus. In other words, record which control has the focus before the focusing event is fired. That's possible in Winforms with the IMessageFilter interface.
Add a new class to your project and paste the code shown below. Compile. Drop the new control from the top of the toolbox onto your form, replacing your existing buttons.
using System;
using System.Windows.Forms;
class CalculatorButton : Button, IMessageFilter {
public string Digit { get; set; }
protected override void OnClick(EventArgs e) {
var box = lastFocused as TextBoxBase;
if (box != null) {
box.AppendText(this.Digit);
box.SelectionStart = box.Text.Length;
box.Focus();
}
base.OnClick(e);
}
protected override void OnHandleCreated(EventArgs e) {
if (!this.DesignMode) Application.AddMessageFilter(this);
base.OnHandleCreated(e);
}
protected override void OnHandleDestroyed(EventArgs e) {
Application.RemoveMessageFilter(this);
base.OnHandleDestroyed(e);
}
bool IMessageFilter.PreFilterMessage(ref Message m) {
var focused = this.FindForm().ActiveControl;
if (focused != null && focused.GetType() != this.GetType()) lastFocused = focused;
return false;
}
private Control lastFocused;
}

Control focusedCtrl;
//Enter event handler for all your TextBoxes
private void TextBoxesEnter(object sender, EventArgs e){
focusedCtrl = sender as TextBox;
}
//Click event handler for your btnNum1
private void btnNum1_Click(object sender, EventArgs e)
{
if (focusedCtrl != null){
focusedCtrl.Focus();
SendKeys.Send("1");
}
}

you have an event called lostFocus you can use
button1.LostFocus +=new EventHandler(dataGridView1_LostFocus);
and in the event:
Control lastFocused;
void dataGridView1_LostFocus(object sender, EventArgs e)
{
lastFocused = sender as Control;
}
in that way you can always know what is the Control that was focused previously
now, correct me if i'm wrong, but you do it for the SendKeys.Send("1"); to know which textBox need to receive the number. for that you can use GotFocus event and register only the textBoxs to it.
you can also do what windows is doing and use just one textbox like here:
if it's fits your needs

What about using this with the parameter forward = false?
Control.SelectNextControl Method
You'd probably call it on your "custom Number Keypad control".

In the WinForms DevExpress XtraWizard control, how can one hide the back button?

I know that if I set the WizardStyle of an XtraWizard control to WizardAero, it will remove or hide the back button from the first page instead of simply disabling it, as can be seen here. I want the same behaviour, but I want to keep the WizardStyle as Wizard97.
Is this possible, and if so, how?

One way to do this would be to use the CustomizeCommandButtons event on the WizardControl.
private void wizardControl1_CustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
e.PrevButton.Visible = false;
}
If you only want to hide it on the first page
private void wizardControl1_CustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
if(wizardControl1.SelectedPageIndex == 0)
e.PrevButton.Visible = false;
}
It seems like it will reset the visibility each time (so you don't need to toggle it back on). Anyway, I think this is what you're looking for.
http://documentation.devexpress.com/#WindowsForms/DevExpressXtraWizardWizardControl_CustomizeCommandButtonstopic

You can also set your own fields to the wizard buttons and then use these anywhere in your code. This will, for example, allow you to hide/disable the "Next" button until all fields page have been completed.
private void NodeConfigurationWizardCustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
_nextButton = e.NextButton;}
private void GetRowsButtonClick(object sender, EventArgs e)
{
var rowList = ServiceClient.GetAvailableRows();
var rowsReturned = rowList.Count > 0;
_nextButton.Button.Enabled = rowsReturned ;}

Tabpage control leave

I have a tab control and 3 tabpages in it. ( C#)
if i am in tab 2, and edit a text box value
and then click tab 3, i need to validate what was enetered in the text box.
if correct i should allow to to switch to tab 3 else should remain in tab 2 it self
how do i achieve this?
iam curently handling the "leave" event of the tabpage2,
i validate the text box value there and if found invalid
i set as tabcontrol.Selectedtab = tabpage2; this does
the validation but switches to new tab! how could i restrict the navigation.
I am a novice to C#, so may be i am handling a wrong event!
Here is the relevant code:
private void tabpage2_Leave(object sender, EventArgs e)
{
if (Validatetabpage2() == -1)
{
this.tabcontrol.SelectedTab =this.tabpage2;
}
}

While the other approaches may work, the Validating event is designed specifically for this.
Here's how it works. When the SelectedIndex of the tab control changes, set the focus to the newly selected page and as well as CausesValidation = true. This ensures the Validating event will called if the user tries to leave the tab in any way.
Then do your normal validation in a page specific Validating event and cancel if required.
You need to make sure to set the initial selected tab page in the Form Shown event (Form_Load will not work) and also wire up the tab page specific validating events.
Here's an example:
private void Form_Shown(object sender, System.EventArgs e)
{
// Focus on the first tab page
tabControl1.TabPages[0].Focus();
tabControl1.TabPages[0].CausesValidation = true;
tabControl1.TabPages[0].Validating += new CancelEventHandler(Page1_Validating);
tabControl1.TabPages[1].Validating += new CancelEventHandler(Page2_Validating);
}
void Page1_Validating(object sender, CancelEventArgs e)
{
if (textBox1.Text == "")
{
e.Cancel = true;
}
}
void Page2_Validating(object sender, CancelEventArgs e)
{
if (checkBox1.Checked == false)
{
e.Cancel = true;
}
}
private void tabControl1_SelectedIndexChanged(object sender, System.EventArgs e)
{
// Whenever the current tab page changes
tabControl1.TabPages[tabControl1.SelectedIndex].Focus();
tabControl1.TabPages[tabControl1.SelectedIndex].CausesValidation = true;
}

You can use the TabControl Selecting event to cancel switching pages. Setting e.Cancel to true in the event stops the tabcontrol from selecting a different tab.
private bool _cancelLeaving = false;
private void tabpage2_Leave(object sender, EventArgs e)
{
_cancelLeaving = Validatetabpage2() == -1;
}
private void tabcontrol_Selecting(object sender, TabControlCancelEventArgs e)
{
e.Cancel = _cancelLeaving;
_cancelLeaving = false;
}