Okay so I created a method called KeyCheck(), that should check if a key is pressed (specifically the enter key) and if it is it will press button1.
Unfortunately when I call the method I am unsure what to pass along to it. I want it to know when the enter key is being pressed.
public partial class Form1 : Form
{
public void GameStart()
{
richTextBox1.WordWrap = true;
richTextBox1.SelectionAlignment = HorizontalAlignment.Center;
richTextBox1.Text = "Hello, Welcome to Grandar!";
}
public Form1()
{
InitializeComponent();
GameStart();
//What variable do I pass to KeyCheck Method?
KeyCheck();
}
private void KeyCheck(KeyPressEventArgs k)
{
if (k.KeyChar == (char)Keys.Enter)
{
button1.PerformClick();
}
}
private void richTextBox1_TextChanged(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
}
}
Couple of things to note here:
a) Do you really want to be calling KeyCheck directly as your sample code suggests or should it be wired up as a handler on the form (where the info you're asking will be automatically provided - will require a change in signature to align with the standard handlers as you have in some of your other methods).
b) I don't think you'll be able to call the KeyCheck method like you're doing unless you hook up another event to capture the keypress and then pass it to this method, by newing up a new KeyPressEvent(...)
Therefore, to answer your question, I think you'll want something like (pseudo-code)
public Form1()
{
InitializeComponent();
GameStart();
// Wire up a handler for the KeyPress event
this.KeyPress += KeyCheck;
}
private void KeyCheck(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Enter)
{
button1.PerformClick();
}
}
Check out this page: https://msdn.microsoft.com/en-us/library/system.windows.forms.control.keypress(v=vs.110).aspx
You'll want something similar to your other methods, with the sender object and the event args.
if (e.KeyCode < Keys.Enter) {
//Your logic
}
subscribe to this:
this.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.KeyPress_Method);
and the method to check the Enter key:
void KeyPress_Method(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)13) // enter key
{
// your code
}
}
Related
So, apparently I had some problem when handling keys such as F10 or F11.
I want to move the focus from current textbox into another textbox, but not in one particular textbox. So, I wrote some code to handle key:
private void checkKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
buyerName.Focus();
}
else if (e.KeyCode == Keys.F11)
{
discount.Focus();
}
}
But, if I put this into individual textbox, which kinda hassle to me. Is there any method to listen key whether in global userControl or textbox?
Edit : here's my structure that I want to ask :
Form-
|-User Control
|-TextBox
Edit 2 : here's some image might help img
To use a global keyboard listener in Winforms, you just need to add a handler to KeyUp action for the main form itself:
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true; //To use F10, you need to set the handled state to true
} else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
}
}
Then make sure that the KeyPreview property on the main form is set to True.
The issue with the application freezing when pressing F10 is because it is waiting for another consecutive action. To bypass this simply set the Handled property on the keyevent to TRUE. This releases the unresolved event.
This is my entire form class, refactored to use a helper method as you are refering to. This works fine. But you have to make sure that the KeyPreview property on your form is True, unless your keypresses will not be matched to your event handlers.
namespace KeyTest
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
CheckKeys(e);
}
private void CheckKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true;
}
else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
e.Handled = true;
}
}
}
}
Now in your comment you are mentioning a UserControl, if you want that, then you need to create an instance method on your UserControl class, and pass the event to that from your global keyboard event handler on your main form.
public partial class UserControl1 : UserControl
{
public UserControl1()
{
InitializeComponent();
}
public void HandleKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true;
}
else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
e.Handled = true;
}
}
}
Then on your main form:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
CheckKeys(e);
}
private void CheckKeys(KeyEventArgs e)
{
uc1.HandleKeys(e); //Instance method on your user control.
}
}
This then works as intended.
As pointed out in one of the comments, a better way would be to override the ProcessCmdKey method on the Form base class. This would be done like so:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
userControl11.HandleKeys(keyData); // method on the userControl to handle the key code.
base.ProcessCmdKey(ref msg, keyData);
return true;
}
}
The handler on the UserControl stays more or less the same:
public void HandleKeys(Keys keys)
{
if (keys == Keys.F10)
{
nameTB.Focus();
} else if (keys == Keys.F11)
{
emailTB.Focus();
}
}
Whether this is a more correct way of doing it, I am unsure of. They certainly both accomplish the same result. The documentation shows the first method in for handling keyboard events at the form level here:
How to handle keyboard input
But states here that the ProcessCmdKey method is to provide additional handling of shortcuts and MDI accellerators.
ProcessCmdKey
I will leave that up to you to decide what is the best for your scenario. But keep it in to show how you would use it should you choose to.
You can hook up to the KeyUp event of your form.
That way, any key pressed while your form is focused will be send to you (if the control didn't handle the key).
Thanks to #Espen and #reza-aghaei for handling keys into main form. Unfortunately, I still didn't managed find a way to focus to designated textbox inside a UserControl. However, I make some dirty method which kinda crappy and un-efficient by searching child control from it's parent
//MainForm.cs
if(yourUserControl.Name)//Do some check for targeted userControl, if null can cause NullReferenceException
{
if (e.KeyCode == Keys.F10)
{
this.Controls.Find("textboxName", true).First().Focus();
e.Handled = true;
}
}
Today I'm having a problem with the keyup event not working on a custom theme.
public Main()
{
InitializeComponent();
tbResolveS2I.KeyUp += new KeyEventHandler(tbResolveS2I_KeyUp);
tbResolveI2S.KeyUp += new KeyEventHandler(tbResolveI2S_KeyUp);
this.KeyPreview = true;
}
private void tbResolveS2I_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
btnResolveS2I_Click(sender, e);
e.SuppressKeyPress = true;
}
}
When I hit enter on my keyboard it sends both textboxes to do the same result. What i mean is if i hit enter on the first textbox it will act like I'm pressing enter on the other textbox aswell
If you want different events to perform the same thing you could add that code to a method and just call that method from the controls event method.
Also in the theme pack you are using, the button extends from Control and does not have a PerformClick() method.
example:
public Main() {
InitializeComponent();
KeyUp += new KeyEventHandler(Main_KeyUp);
this.KeyPreview = true;
}
private void Main_KeyUp(object sender, KeyEventArgs e) {
if(e.KeyCode == Keys.Enter) {
CustomCode();
e.SuppressKeyPress = true;
}
}
private void btnResolveS2I_Click(object sender, EventArgs e) {
CustomCode();
}
private void CustomCode() {
//Perform code here
}
}
I would like to know how I can make a PictureBox click using the Text box .
private void textBox2_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Enter)
{
// I wanna a method to click on PictureBox1 here
}
}
Calling an event from another event is a bad idea. (In fact, calling a user driven event in your code is always a bad idea).
If you want to run some code, put it in its own method and call it from each event.
private void textBox2_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Enter)
{
MyPictureBoxCode();
}
}
private void PictureBox_Click(object sender, EventArgs e)
{
MyPictureBoxCode();
}
private void MyPictureBoxCode()
{
//common code
}
The PictureBox Click event and the Textbox2 Click event must be tied in from your designer.cs.
I want to create an event when every key stroke on the keyboard happened. So far I did this:
namespace WindowsFormsApplication1
{
public partial class SpaceInvadors : Form
{
SpaceInvadors sInvaders;
public SpaceInvadors()
{
InitializeComponent();
KeyStroke keyStroke = new KeyStroke();
sInvaders=new SpaceInvadors(keyStroke);
}
public SpaceInvadors(KeyStroke keyStroke)
{
keyStroke.keyStroked += Form1_KeyDown;//How does that chaining to the event work?
keyStroke.keyStroked += Form1_KeyUp;
}
private void Form1_KeyDown(object sender, KeyArgs e)
{
if (e.KeyCode == Keys.Q)
{
Application.Exit();
}
}
}
public class KeyStroke
{
public event EventHandler<KeyArgs> keyStroked;
public void Add(Keys key)
{
// I need to know how to obtain this key:
KeyArgs keyAr = new KeyArgs(key);
keyRisen(keyAr);
}
public void keyRisen(KeyArgs kA)
{
if (keyStroked != null)
keyStroked(this, kA);
}
}
public class KeyArgs : EventArgs
{
public Keys KeyCode { get; set; }
public KeyArgs(Keys key)
{
KeyCode = key;
}
}
Also, how can I all the time listen to what keys were pressed, and not only once
For your question
"Also, how can I all the time listen
to what keys were pressed, and not
only once"
I see that you have already used Form.KeyDown event to close your game if 'q' was pressed:
private void Form1_KeyDown(object sender, KeyArgs e)
{
if (e.KeyCode == Keys.Q)
{
Application.Exit();
}
}
Ok you can add more keys to your method:
private void Form1_KeyDown(object sender, KeyArgs e)
{
if (e.KeyCode == Keys.Q)
{
Application.Exit();
}
else if (e.KeyCode == Keys.Up)
spaceInvaders.MoveUp();
}
For the chaining, I think that class KeyStoke manage playing interface. Because KeyDown event is used to determine what key was pressed. I advise you more learning to events and delegates.
If I understand correct you are writing a game, The space invaders! :)
I dont think that this approach is good for game. The most appropriate and commonly used approach is to use GetKeyboardState function. To achive good ingame results with this function you should create timer and check key states periodically. And I recomment you perform rendering also in timer routine.
If some reasons prevents you to use GetKeyboardState I will recomend you to use PreviewKeyDown
My question is:
How can I disable the hold a key down in a textbox control using C#?
e.g Boxxxxxxxxxxxxxxxxxxxxx
I don't want to allow user to repeat any character from the keyboard.
Any suggestion?
thanks
Just an extra note for everyone using KeyDown and KeyUp events to suppress key repeat. If you do this you need to exclude catching meta keys like Alt/Shift etc otherwise when those keys are held down the actual key you want will not be sent since this is a two key combination and KeyDown and KeyUp events catch all keys.
This applies to all two-key combinations.
I did not add all of the meta keys to the following example, just the most common ones.
You can easily add your own keys by adding them to the collection.
Extending on the post from BFree:
public partial class Form1 : Form
{
private static readonly System.Collections.Generic.ICollection<System.Windows.Forms.Keys) ExcludeKeys = new System.Collections.Generic.HashSet<System.Windows.Forms.Keys)()
{
System.Windows.Forms.Keys.None,
System.Windows.Forms.Keys.Shift,
System.Windows.Forms.Keys.ShiftKey,
System.Windows.Forms.Keys.LShiftKey,
System.Windows.Forms.Keys.RShiftKey,
System.Windows.Forms.Keys.Alt,
System.Windows.Forms.Keys.Control,
System.Windows.Forms.Keys.ControlKey,
System.Windows.Forms.Keys.LControlKey,
System.Windows.Forms.Keys.RControlKey,
System.Windows.Forms.Keys.CapsLock,
System.Windows.Forms.Keys.NumLock,
System.Windows.Forms.Keys.LWin,
System.Windows.Forms.Keys.RWin
}
private bool isKeyPressed = false;
public Form1()
{
InitializeComponent();
this.textBox1.KeyDown += new KeyEventHandler(textBox1_KeyDown);
this.textBox1.KeyUp += new KeyEventHandler(textBox1_KeyUp);
}
void textBox1_KeyUp(object sender, KeyEventArgs e)
{
if (!ExcludeKeys.Contains(e.KeyCode))
{
isKeyPressed = false;
}
}
void textBox1_KeyDown(object sender, KeyEventArgs e)
{
if (!ExcludeKeys.Contains(e.KeyCode))
{
e.SuppressKeyPress = isKeyPressed;
isKeyPressed = true;
}
}
}
You can use the SupressKeyPress property on KeyEventArgs:
public partial class Form1 : Form
{
private bool isKeyPressed = false;
public Form1()
{
InitializeComponent();
this.textBox1.KeyDown += new KeyEventHandler(textBox1_KeyDown);
this.textBox1.KeyUp += new KeyEventHandler(textBox1_KeyUp);
}
void textBox1_KeyUp(object sender, KeyEventArgs e)
{
isKeyPressed = false;
}
void textBox1_KeyDown(object sender, KeyEventArgs e)
{
e.SuppressKeyPress = isKeyPressed;
isKeyPressed = true;
}
}
bool prevent = false;
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
e.SuppressKeyPress = prevent;
}
private void textBox1_KeyUp(object sender, KeyEventArgs e)
{
prevent = false;
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
prevent = true;
}
I'm not familiar with the specifics in c# but I imagine something like:
while (keyIsDown){
//do nothing
}
would work. I would be surprised if there is no way to keep track of a key being pressed.