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Detect keyboard input and mouse activity on a single form

I have this below form and I want to detect key-strokes and any mouse clicks on the button.
For example, if I press S on my keyboard, message will show START and keypress will display keyboard press. The same thing happen when mouse-click on START button, except that keypress will display START BTN.
Here is my button code. If I only do for button or only IsKeyDown it works fine, but when I combine both in one form, they go haywire.
private void btnStart_Click(object sender, EventArgs e)
{
lblKeypress.Text = "START BTN";
lblmessage.Text = "START";
}
Here is my Keyboard.IsKeyDown code:
private void Form1_KeyPress(object sender, KeyPressEventArgs e)
{
if (Keyboard.IsKeyDown(Key.S))
{
lblKeypress.Text = "Keyboard Press";
lblmessage.Text = "START";
}
}
Please help, thanks.

try this code
private void Form1_KeyDown(object sender,
EventArgs e){
if (e.KeyData == Keys.S){
lblKeypress.Text = "Keyboard Press";
lblmessage.Text = "START";
}
}

Make sure that in your Form you set KeyPreviewProperty to TRUE
In Form1.Designer.cs
this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.form_keydown);
private void form_keydown(object sender, KeyEventArgs e)
{
int keyVal = (int)e.KeyValue;
keyValue = -1;
if ((keyVal >= (int)Keys.S))
{
keyValue = (int)e.KeyValue - (int)Keys.S;
lblKeypress.Text = "Keyboard Press";
lblmessage.Text = "START";
}
}
Note:
Ensure you do not have any unrelated WPF namespaces`
(Keyboard.IsKeyDown(Key.S)) is a WPF approach, in WinForms you are better off using combination of e.KeyValue & Keys

How to design a keypad in C#?

I am new to C# and I am planing to design my own keypad but I don't know how/where to start. as shown in photo, I have 4 textBoxes the keypad buttons.
The first problem came into my mind was: how can I detect the cursor location (which textBox is the cursor in?).
So for example if I had only one textbox then it is easy I could write inside button1 : textBox1.text = "1" and inside button2 : textBox1.text = "2" and inside button_A : textBox1.text = "A".... and so on but I have 4 textBoxes and it is confusing.
Can you please provide me with an idea or what to write inside each button to print its value in the textbox which the cursor is in.
Thank you professionals.

Firstly, have a textbox that represents the one that is selected (outside of subroutines but inside the class):
TextBox SelectedTextBox = null;
And then make the "Click" event of each TextBox look like this:
private void textBoxNUM_Click(object sender, EventArgs e)
{
SelectedTextBox = sender as TextBox;
}
And then make the "Click" event of each Button look like this:
private void buttonNUM_Click(object sender, EventArgs e)
{
if (SelectedTextBox != null)
{
SelectedTextBox.Text = buttonNUM.Text;//Or set it to the actual value, whatever.
}
}
Or if that one doesn't work, this should.
private void buttonNUM_Click(object sender, EventArgs e)
{
if (SelectedTextBox != null)
{
(SelectedTextBox as TextBox).Text = buttonNUM.Text;//Or set it to the actual value, whatever.
}
}

To check if a textbox is focused you can do
if(textbox1.Focused)
{
//Print the value of the button to textbox 1
}
else if (textbox2.Focused)
{
//Print the value to textbox 2
}
UPDATE:
Since the textbox will lose focus when you click the button, you should have a temporary textbox (ie lastTextboxThatWasFocused) which is saved to everytime a textbox gains focus. Write an OnFocused Method and do something like
public void Textbox1OnFocused(/*Sender Event Args*/)
{
lastTextboxThatWasFocused=textbox1;
}
Then on button click you can do
if(lastTextboxThatWasFocused.Equals(textbox1))
{
//ETC.
}

You can give something along these lines a try. Create a generic click handler for the buttons and then assign the value to a textbox the text from the button, which happens to be the value. You can check which box was the last one focused in the TextBoxes' Click event. Create a global variable to store which one and use it in the below method.
private TextBox SelectedTextBox { get; set; }
private void NumericButton_Click(object sender, EventArgs e)
{
var clickedBox = sender as Button;
if (clickedBox != null)
{
this.SelectedTextBox.Text += clickedBox.Text;
}
}
private void TextBox_Click(object sender, EventArgs e)
{
var thisBox = sender as TextBox;
if (thisBox == null)
{
return;
}
this.SelectedTextBox = thisBox;
}

Try this code:
TextBox LastTxtBox;
private void textBox_Enter(object sender, EventArgs e)
{
LastTxtBox = sender as TextBox;
}
private void button_Click(object sender, EventArgs e)
{
LastTxtBox.Text = this.ActiveControl.Text;
}
Add textBox_Enter function to all textboxes enter event.
Add button_Click to all buttons click event.

Button Enter Event
Control _activeControl;
private void NumberPadButton_Click(object sender, EventArgs e)
{
Button btn = (Button)sender;
if (_activeControl is TextBox || _activeControl is RichTextBox)
{
_activeControl.Text += btn.Text;
if (!_activeControl.Focused) _activeControl.Focus();
}
}
TextBox or RihTextBox Enter Event
private void TextBoxEnter_Click(object sender, EventArgs e)
{
_activeControl = (Control)sender;
}

how to reset the focus to last entered textbox in windows application

I have two TextBoxes and a button control in the form. When the button is clicked the name of the last entered TextBox should be displayed in a MessageBox. At the same time I need to reset the focus to last entered TextBox.
string str=string.Empty;
bool foc;
In button click I wrote the following code
if (MessageBox.Show("You want to reset or continue", "control",
MessageBoxButtons.OKCancel) == DialogResult.Cancel)
{
if (foc== true)
{
textBox1.Focus();
}
else
{
textBox2.Focus();
}
}
When I clicks on cancel button the focus should be into textbox which is entered at last
private void textBox1_Enter(object sender, EventArgs e)
{
str = textBox1.Name;
foc= textBox1.Focus();
}
private void textBox2_Enter(object sender, EventArgs e)
{
str= textBox2.Name;
foc= false;
}
Other than the above lines of code is there any other possibility to focus into the textbox, but when number of textboxes increases how i need to write the conditions.
If I am having textbox,combobox,listbox,checkbox or any other controls in the form then how to find in which control the user enterd at last and set focus to that control by using any function instead of writing in every control Enter event

You can handle Leave event of the TextBoxes to store the Last TextBox Control.
Try this:
this.btnSubmit.Click += new System.EventHandler(this.Submit_Click);
this.btnCancel.Click += new System.EventHandler(this.Cancel_Click);
this.textBox1.Leave += new System.EventHandler(this.textBox1_Leave);
this.textBox2.Leave += new System.EventHandler(this.textBox2_Leave);
TextBox txtLast = new TextBox();
private void textBox1_Leave(object sender, EventArgs e)
{
txtLast = (TextBox)sender;
}
private void textBox2_Leave(object sender, EventArgs e)
{
txtLast = (TextBox)sender;
}
private void Submit_Click(object sender, EventArgs e)
{
MessageBox.Show(txtLast.Text);
}
private void Cancel_Click(object sender, EventArgs e)
{
txtLast.Focus();
}

public bool textBox1WasLastFocused = false, textBox2WasLastFocused = false; // Global Declaration
void textBox2_GotFocus(object sender, EventArgs e)
{
textBox2WasLastFocused = true;
textBox1WasLastFocused = false;
}
void textBox1_GotFocus(object sender, EventArgs e)
{
textBox1WasLastFocused = true;
textBox2WasLastFocused = false;
}
private void button1_Click(object sender, EventArgs e)
{
if (textBox1WasLastFocused)
MessageBox.Show("textbox1 was ladst focused !");
else if(textBox2WasLastFocused)
MessageBox.Show("textbox2 was ladst focused !");
}

How to gray out default text in textbox?

When I click on a textbox, I want the default text to disappear. Is there any other property that would work for this purpose?

The following Will set Default text in Gray color. Also When you leave the textbox as blank, again set default text to the textbox.
private void Form1_Load(object sender, EventArgs e)
{
this.textBox2.Enter += new EventHandler(textBox2_Enter);
this.textBox2.Leave += new EventHandler(textBox2_Leave);
textBox2_SetText();
}
protected void textBox2_SetText()
{
this.textBox2.Text = "Default Text...";
textBox2.ForeColor = Color.Gray;
}
private void textBox2_Enter(object sender, EventArgs e)
{
if (textBox2.ForeColor == Color.Black)
return;
textBox2.Text = "";
textBox2.ForeColor = Color.Black;
}
private void textBox2_Leave(object sender, EventArgs e)
{
if (textBox2.Text.Trim() == "")
textBox2_SetText();
}

Add a method to the GotFocus event of the TextBox that will change the Text property to ""
private void Form1_Load(object sender, EventArgs e) {
this.textBox1.GotFocus += new EventHandler(textBox1_Focus);
this.textBox1.Text = "some default text...";
}
protected void textBox1_Focus(Object sender, EventArgs e) {
textBox1.Text = "";
}

It sounds like you are wanting a Watermark in your Textbox.
See these articles.
http://www.codeproject.com/Articles/319910/Custom-TextBox-with-watermark
Watermark in System.Windows.Forms.TextBox
and if you are using wpf something like this http://msdn.microsoft.com/en-us/library/bb613590.aspx

C# Windows Forms app - Clear ComboBox selected text from another ComboBox

Windows Forms application (c#).
I have two ComboBoxes.
If I select an item in one, I want the text in the other one to be blank.
This is what I have:
private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox2.Text = "";
}
private void ComboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox1.Text = "";
}
... but as you can see, when I make a selection in one, the text in both ComboBoxes get cleared.
How to accomplish this?
Thank you.

Try setting the ComboBox.SelectedIndex to -1
A zero-based index of the currently selected item. A value of negative
one (-1) is returned if no item is selected.
or rather based on your specifications try something lie
private bool changed = false;
private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
if (!changed)
{
changed = true;
ComboBox2.Text = "";
changed = false;
}
}
private void ComboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
if (!changed)
{
changed = true;
ComboBox1.Text = "";
changed = false;
}
}