I am trying to control user input when he/she wants to edit a treeNode. I don't want him to be able to write numbers (or even better not write a number at given index of the text but thats a bonus)
What I did was make a boolean on the mainWindow that determines if the user is editing the treeNode or not like this:
void Tree_AfterLabelEdit(object sender, System.Windows.Forms.NodeLabelEditEventArgs e) {
isEditing = false;
}
void Tree_BeforeLabelEdit(object sender, System.Windows.Forms.NodeLabelEditEventArgs e) {
isEditing = true;
}
private void Tree_KeyDown(object sender, KeyEventArgs e) {
control input. (e.Handled = true when keyDown is a number.)
}
This is what I tried but the event keydown is only called when I am NOT editing a treenode. So it falls out of purpose. (I use keydown already to handle arrow key events but I want to do both.)
Tried with keypress aswell to no avail.
The TreeView does not have any mechanism to control the LabelEdit part. Even if you can handle the KeyDown part of the Label to prevent numbers, you would still have to inspect the contents on the AfterLabelEdit because the user can "paste" numbers into the field as well. It's best to just control it during the AfterLabelEdit event:
private void treeView1_AfterLabelEdit(object sender, NodeLabelEditEventArgs e)
{
foreach (char c in e.Label)
{
if (char.IsNumber(c))
e.CancelEdit = true;
}
}
Related
I have two text boxes in windows form.
Also one disabled button.
How I can do validation text box:
if field is empty then disable button
if value inside field is less then 5 then disable button
other case - enable button
I tried this on event TextChange, but when I tried to enter value 43 I get notification, because event TextChange works after each typing symbols.
Code:
private void textBox2_TextChanged(object sender, EventArgs e)
{
if (String.IsNullOrEmpty(textBox2.Text))
{
button6.Enabled = true;
}
}
If you don't want to validate each time a key is pressed but would rather validate when the user leaves the field, instead of hooking into the TextChanged event, hook into the Leave event.
private void textBox2_Leave(object sender, EventArgs e)
{
button6.Enabled = !(string.IsNullOrEmpty(textBox2.Text)) && textBox2.Text.Length >= 5;
if (!button6.Enabled)
{
textBox2.Focus();
}
}
Update your event handle like this :
private void textBox2_TextChanged(object sender, EventArgs e)
{
button6.Enabled =
!String.IsNullOrEmpty(textBox2.Text) && textBox2.Text.Length > 5
}
As for disabling the button on start up, you just set button6 to be disabled by default.
Or, invoke your validation in your constructor :
textBox2_TextChanged(null, null);
Neither TextChanged nor Leave events are appropriate for this. The proper event is called (surprise:-) Validating. You need to set e.Cancel = true if validation is wrong. More info: https://msdn.microsoft.com/en-us/library/system.windows.forms.control.validating(v=vs.110).aspx
I have a program containing multiple C# Forms TextBoxes. I've set up Hotkeys for the entire form activating certain functions. My problem is that my Hotkeys have been set onto the Form KeyDown event and they activate if I write something on a TextBox.
Example: One Hotkey might be I. Everytime I write the letter onto a textbox the Hotkey activates.
Alterior solutions and problems: I've thought about putting a Key in front of the Hotkey like CTRL+Hotkey, but these also present problems as CTRL+C is Windows Copy command etc. SHIFT is an UpperKey button.
Question: Can I prevent Hotkeys from activating when I am writing onto a TextBox without having to go through all of them in the form?
EDIT: Some code as requested. The button codes come from a stored XML file or the Hotkeys Form+Class (separate) where I've set up a window for them.
public Hotkeys hotkeysForm = new Hotkeys();
void Form1_KeyDown(object sender, KeyEventArgs e)
{
toggleInformation = hotkeysForm.toggleInformation;
if (e.Control && e.KeyCode == toggleInformation)
{
showInfo(true);
}
else if (e.KeyCode == toggleInformation)
{
if (!isInfoActive)
showInfo();
else
hideInfo();
}
}
You can disable hotkeys while texbox is an active control. Add the Enter and Leave events for all textboxes:
private void textBox_Enter(object sender, EventArgs e)
{
KeyPreview = false;
}
private void textBox_Leave(object sender, EventArgs e)
{
KeyPreview = true;
}
You should try this hack, if it could solve your problem,
Create a Extented TextBox and use it in your code. you can handle whether to write the pressed key in textbox or not in hotkeyPressed check.
public class ETextBox : System.Windows.Forms.TextBox
{
protected override void OnKeyDown(System.Windows.Forms.KeyEventArgs e)
{
if (hotKeyPressed) // this is the condition when you don't want to write in text.
{
//Do whatever you want to do in this case.
}
else
{
base.OnKeyDown(e);
}
}
}
is there a way to allow editing a string partially in c# and wpf textbox?
somthing , if the contents of the TextBox were for example
"http://xxxx.xxx/xx/path?param1=xxx¶m2=xxx"
the x can be replaced with whatever length but any thing else is constant and cannot be edited in the textbox, any way to achive such thing?
There are two relevant events that you can handle on the TextBox; the PreviewKeyDown and the PreviewTextInput events. By handling these two events, you will have complete control over what the user can and can't edit in the TextBox. Of course you will need to work out the logic inside, but the event handlers are the tool to enable you to do what you want:
private void TextBox_PreviewKeyDown(object sender, KeyEventArgs e)
{
// Do your text filtering here using e.Key and e.Handled
}
private void TextBox_PreviewTextInput(object sender, TextCompositionEventArgs e)
{
// Do your text filtering here using e.Text and e.Handled
}
I have numeric buttons which when pressed display the number in different text boxes. Now my problem is that i want check which textbox has focus so that the number pressed will be entered in that textbox.
My Code:
private void btn_one_Click(object sender, EventArgs e)
{
if (txt_one.Focused==true)
{
txt_one.Text += btn_one.Text;
}
else if (txt_two.Focused==true)
{
txt_two.Text += btn_one.Text;
}
}
Now my problem is that the above code is not working what is wrong and what will be the solution? I even used something like this
private void btn_one_Click(object sender, EventArgs e)
{
if (txt_one.Focus()==true)
{
txt_one.Text += btn_one.Text;
}
else if (txt_two.Focus()=true)
{
txt_two.Text += btn_one.Text;
}
}
In both the above cases the text is entered in both the text boxes. Any solutions.
This problem is a little tricky (with my experience dealing with Enter, Focus, LostFocus, Leave events, all these things sometimes make your head ache a lot and you should avoid dealing with them if possible), at the time you click your Button, the current Focused control you can know is exactly the Button (ActiveControl is one short way to access it). So the solution is we have to record the track of focused TextBox, hold it in a reference and use it when needed. In fact if the control other than one of your TextBoxes is focused, we have to reset the variable lastFocused to null:
TextBox lastFocused;
//Enter event handler for all your TextBoxes
private void TextBoxes_Enter(object sender, EventArgs e){
lastFocused = sender as TextBox;
}
//Click event handler for your button
private void btn_one_Click(object sender, EventArgs e){
if(lastFocused != null) lastFocused.Text += btn_one.Text;
}
I know this has been asked hundred of times, but I haven't been able to find a solution that helps me. I'm using a barcode scanner and I want to be able to get the keys that are typed using just the keydown events. For some reason, I can't use both keydown and keypress events (my keypress events won't run).
I need to be able to get the characters, including hyphens, uppercase letters and dots and also need to detect the enter key.
These are my listeners:
form.KeyDown += new KeyEventHandler(Input_KeyDown);
form.KeyPress += new KeyPressEventHandler(Input_KeyPress);
And these are my methods:
private void TimedOut(object sender, EventArgs e)
{
_barcode = "";
}
private void Input_KeyDown(object sender, KeyEventArgs e)
{
_timer.Stop();
_timer.Start();
if (e.KeyData == Keys.Enter)
{
if (!_barcode.Equals(""))
{
this.BarcodeScanned(_barcode, new EventArgs());
}
}
else
{
}
}
private void Input_KeyPress(object sender, KeyPressEventArgs e)
{
_timer.Stop();
_timer.Start();
_barcode += e.KeyChar;
}
Your code above works...on a blank form. However there are several things that can interfere with the key events, especially when there are other controls on the page. Make sure that
The AcceptButton property isn't set on the form (this will trap the Enter key)
That there are no controls on the form with TabStop set to true (might not be viable but give it a go)
That the form has focus when you're typing (unlikely given the description but check anyway)
That focus is not otherwise on any control in the form when typing, e.g., a TextBox
That no other controls are trying to process the KeyPress or KeyDown events and that no other custom events are configured/set anywhere else in your code
One thing I notice is that you are registering the events like so;
form.KeyDown += new KeyEventHandler(Input_KeyDown);
This implies that you are instantiating this form from another place and trying to get it to send its key events to the calling code. Are you sure that the form instance is persisted/saved to a private class level variable or some such?