I'm trying to get a screen in silverlight where the user can enter their own text and add line breaks as neccesary. The problem is that whenever they hit return inside of a text block, nothing happens. Is there some way around this?
Thanks
Nevermind, I figured out you needed to set the AcceptsReturn property to true.
[Edit: For whoever voted my answer down -- the question was "how do you capture enter in a text block". The text block element does not have an AcceptsReturn attribute.]
You should be able to trap for the Enter key and insert a newline character.
private string textBuffer = "";
private void TextBlock_KeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Enter)
{
textBuffer += Environment.NewLine;
}
else
{
textBuffer += e.Key.ToString();
}
Text.Text = textBuffer;
e.Handled = true;
}
About the answer from another Timothy, TextBlock is not for typing. Are you sure you really don't want to use a TextBox instead?
Related
I am using a Barcode reader to get bar code from products .
i get the code in a textfield . and i put textchanged event on that textbox .
but the problem is that when bar code puts it value ( for example if bar code is 5 digit ) then textchanged event is fired five times .
how to get ride of this thing ???
You should be able to program your Barcode reader to output a prefix character and a suffix character (one output before the scanned value and one afterwards). Let's say that you set it up to output an asterisk (*) before the scanned data value and output a carriage return (CR) afterwards. Attach a handler to the TextBox.PreviewTextInput Event and listen out for the asterisk character:
private void PreviewTextInput(object sender, TextCompositionEventArgs e)
{
if (e.Text == "*")
{
e.Handled = true;
// Data input has started
}
}
You can use this to pop up a message saying 'Scanning...', or anything else that you require. Next, attach a handler to the TextBox.KeyUp Event and listen out for the Enter key:
private void KeyUp(object sender, KeyEventArgs e)
{
if (e.Key == Key.Return)
{
string scannedValue = ScanTextBox.Text.Replace("*", string.Empty);
// Do something with scannedValue
}
}
Now the scannedValue variable should contain the scanned barcode value.
In WPF Application I have a textbox.
I set its AcceptsReturn Property to true.
So, I can enter data in multiple lines.
When user press enter in the textbox I want to check :
1) Is the cursor on the last line?
2) If cursor is on the last line then check if thatLine.Text = Nothing?
Something like this?
private void TextBoxOnTextChanged(object sender, TextChangedEventArgs e)
{
TextBox tb = sender as TextBox;
if (tb == null)
{
return;
}
string[] lines = tb.Text.Split(new[] { Environment.NewLine }, StringSplitOptions.None);
if (tb.CaretIndex >= tb.Text.Length - lines.Last().Length)
{
// cursor is on last line
if (string.IsNullOrEmpty(lines.Last()))
{
// cursor is on last line and line is empty
}
}
}
ok is in c# but i don't know the vb syntax..
if you need a translation to vb: http://www.developerfusion.com/tools/convert/csharp-to-vb/ ;-)
I use the TextChanged event of a textbox.
for instance I have the text in the textbox:
"a b"- 2 spaces between a,b
I go in the middle of the 2 spaces, and hit backspace. I can not check by comparing the new text with the old which key was pressed (if backspace or delete was pressed, the newtext is the
same "a b"-1 space between letters.
How can I check which key was pressed?
Why do you care? If you're handling the TextChanged event, you're not supposed to care what about the text was changed, just the fact that it was.
If you need to care about what specifically was changed, you need to handle a lower-level event, like KeyDown:
private void OnKeyDownHandler(object sender, KeyEventArgs e)
{
if (e.Key == Key.Back || e.Key == Key.Delete)
{
// The user deleted a character
}
}
I know this is an old question, but maybe someone will find this helpful.
I used an integer, that counts length of current characters. It updates with the event.
Every time, the event is triggered, I check, if the length of the counter is longer than the current length of the text. If it is, we know, there was something deleted.
private int counter = 0;
private void TextChangedEvent(object sender, TextChangedEventArgs e){
if(counter > textbox.text){
counter = text.Length;
//deleted
}
else{
counter = text.Length;
//added}
Here is the deal: I have a RichTextBox control and it works fine. The problem is that there is a button "Insert Current DateTime" which adds/injects the current datetime into the RichTextBox. The user can enter the datetime anywhere where the caret is pointing. This involves complicated string manipulation and stuff.
Any ideas how to get the current caret position. Whenever I get RichTextBox.CaretPositon it seems it is pointing to the start of the RichTextBox and not where the actual caret is.
UPDATE 1:
The date time button click code:
private void DateTimeStampButton_Click(object sender, RoutedEventArgs e)
{
//TextRange tr = new TextRange(textBox.Selection.Start, textBox.Selection.End);
var tr = new TextRange(textBox.Document.ContentStart, textBox.Document.ContentEnd);
if(tr.Text.Length == 2)
{
if(tr.Text == "\r\n")
{
tr.Text = tr.Text.TrimStart(new[] { '\r', '\n' });
}
}
textBox.CaretPosition.InsertTextInRun(DateTime.Now.ToShortDateString() + " " + DateTime.Now.ToShortTimeString() + ": ");
DateTimeStampButton.Focusable = false;
}
private void SharpRichTextBox_LostFocus(object sender, RoutedEventArgs e)
{
SetValue(TextProperty, Text);
var binding = BindingOperations.GetBinding(this, TextProperty);
if (binding == null) return;
if (binding.UpdateSourceTrigger == UpdateSourceTrigger.Default || binding.UpdateSourceTrigger == UpdateSourceTrigger.LostFocus)
{
// if (TextProperty != null) BindingOperations.GetBindingExpression(this, TextProperty).UpdateSource();
}
}
public string Text
{
get
{
var newValue = new TextRange(Document.ContentStart, Document.ContentEnd).Text.RemoveNewLineAndReturn();
return newValue;
}
set
{
if (!String.IsNullOrEmpty(value))
{
SetValue(TextProperty, value.RemoveNewLineAndReturn());
Document.Blocks.Clear();
Document.Blocks.Add(new Paragraph(new Run(value)));
OnPropertyChanged("Text");
}
}
}
UPDATE 2:
Turned out the problem was with the DateTime button being Focusable. I turned it to be not focusable and it worked as expected. When focus was lost on the RichTextBox it was resetting the caret position. It happened only once since in the code the btn_DateTime was dynamically being set as Focusable = false. I placed Focusable = false in XAML and everything worked fine from the start.
I'm using this code to successfully do what you are attempting:
private void insertNowButton_Click(object sender, RoutedEventArgs e)
{
//NOTE: The caret position does not change.
richTextBox1.CaretPosition.InsertTextInRun(DateTime.Now.ToString());
}
EDIT: Addressing Update 1
private void DateTimeStampButton_Click(object sender, RoutedEventArgs e)
{
var tr = new TextRange(textBox.Document.ContentStart, textBox.Document.ContentEnd);
if (tr.Text.Length == 2)
{
if (tr.Text == "\r\n")
{
tr.Text = tr.Text.TrimStart(new[] { '\r', '\n' });
}
}
/* Changing the text is the only way I can get the date to insert at the beginning */
tr.Text = "I need a beer at ";
textBox.CaretPosition.InsertTextInRun(DateTime.Now.ToString());
}
It looks like SetValue is changing the text so based on my test that actually changing the text resets the caret, I would agree with you that SetValue is causing the problem...
I tried this solution with WPFToolkit.Extended RichTextBox and it didn't work for me.
However I found another one and thought it would be good to post it in here in case someone else could use it.
My problem was also that the after I clicked a button that is supposed to append text at the caret location, it instead adds it at the beginning of the RichTextBox.
So The solution I found is similar to the one in here -
RichTextBox CaretPosition physical location
Instead of using CaretPosition I used RichTextBox.Selection.Start.InsertTextInRun("SomeText").
It considered the selection's start as the caret position even though no selection was made and therefore was good enough for me.
I hope someone will find this useful :)
This worked for me:
private void InsertText(String text, RichTextBox rtb)
{
rtb.CaretPosition = rtb.CaretPosition.GetPositionAtOffset(0, LogicalDirection.Forward);
rtb.CaretPosition.InsertTextInRun(text);
}
I found the code here:
How do I move the caret a certain number of positions in a WPF RichTextBox?
I am trying to set the MaxLength property on a RichTextBox but it does not seem to work.
Any ideas what might be happening?
The fundamental problem is that the WPF RichTextBox doesn't have a MaxLength property - unlike the Windows.Forms one.
Here's an improvement on #jhony's anwser. If you catch the PreviewKeyDown event and check the length, you also need to allow the user to press Delete and BackSpace after hitting the limit.
// In constructor
this.RichTextBox.PreviewKeyDown += this.EditBox_KeyDown;
private void EditBox_KeyDown(object sender, KeyEventArgs e)
{
if (e.Key != Key.Delete && e.Key != Key.Back)
{
var range = new TextRange(this.RichTextBox.Document.ContentStart, this.RichTextBox.Document.ContentEnd);
if (range.Text.Length > this.MaxLength)
{
e.Handled = true;
return;
}
}
}
You should also allow the arrow keys, because you wouldn't expect them to be disabled.
To disable pasting, put this in the constructor DataObject.AddPastingHandler(this.RichTextBox, this.EditBox_Paste); and
private void EditBox_Paste(object sender, DataObjectPastingEventArgs e)
{
e.CancelCommand();
}
However, you might want to allow pasting unless it breaks the MaxLength, in which case you'll need to check the text being inserted, and the text it is replacing. At that point I decided not to implement a MaxLength in the control, but to handle it with the rest of the validation in the form.
Add this code in yout KeyDown Event.
private void rLetter_KeyDown(object sender, KeyEventArgs e)
{
TextRange tr= new TextRange(rLetter.Document.ContentStart, rLetter.Document.ContentEnd);
if (tr.Text.Length > 4000 || e.Key == Key.Space || e.Key == Key.Enter)
{
e.Handled = true;
return;
}
}
I have some problem, The bug is :
Test this code using copy and paste text max 4000.
Sorry for my English ..