Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>User input in a <code>TextBox</code> can be identified with</p> <ul> <li>Typing : <em>PreviewTextInput event</em></li> <li>Backspace, Delete, Enter : <em>PreviewKeyDown event</em></li> <li>Pasting : <em>DataObject.PastingEvent</em></li> </ul> <p>Combining these three events with a bool flag to indicate if any of the above occured before the <em>TextChanged</em> event and you'll know the reason for the update.</p> <p>Typing and Pasting are easy, but Backspace doesn't always trigger <code>TextChanged</code> (if no text is selected and the cursor is at position 0 for example). So some logic is needed in <em>PreviewTextInput</em>.</p> <p>Here is an Attached Behavior that implements the logic above and executes a command with a bool flag when <code>TextChanged</code> is raised.</p> <pre><code>&lt;TextBox ex:TextChangedBehavior.TextChangedCommand="{Binding TextChangedCommand}" /&gt; </code></pre> <p>And in code you can find out the source for the update like</p> <pre><code>private void TextChanged_Executed(object parameter) { object[] parameters = parameter as object[]; object sender = parameters[0]; TextChangedEventArgs e = (TextChangedEventArgs)parameters[1]; bool userInput = (bool)parameters[2]; if (userInput == true) { // User input update.. } else { // Binding, Programatic update.. } } </code></pre> <p>Here is a small sample project demonstrating the effect: <a href="https://www.dropbox.com/s/n56hp8tryok4m2t/SourceOfTextChanged.zip?dl=0" rel="nofollow noreferrer">SourceOfTextChanged.zip</a></p> <p><em>TextChangedBehavior</em></p> <pre><code>public class TextChangedBehavior { public static DependencyProperty TextChangedCommandProperty = DependencyProperty.RegisterAttached("TextChangedCommand", typeof(ICommand), typeof(TextChangedBehavior), new UIPropertyMetadata(TextChangedCommandChanged)); public static void SetTextChangedCommand(DependencyObject target, ICommand value) { target.SetValue(TextChangedCommandProperty, value); } // Subscribe to the events if we have a valid command private static void TextChangedCommandChanged(DependencyObject target, DependencyPropertyChangedEventArgs e) { TextBox textBox = target as TextBox; if (textBox != null) { if ((e.NewValue != null) &amp;&amp; (e.OldValue == null)) { textBox.PreviewKeyDown += textBox_PreviewKeyDown; textBox.PreviewTextInput += textBox_PreviewTextInput; DataObject.AddPastingHandler(textBox, textBox_TextPasted); textBox.TextChanged += textBox_TextChanged; } else if ((e.NewValue == null) &amp;&amp; (e.OldValue != null)) { textBox.PreviewKeyDown -= textBox_PreviewKeyDown; textBox.PreviewTextInput -= textBox_PreviewTextInput; DataObject.RemovePastingHandler(textBox, textBox_TextPasted); textBox.TextChanged -= textBox_TextChanged; } } } // Catches User input private static void textBox_PreviewTextInput(object sender, TextCompositionEventArgs e) { TextBox textBox = sender as TextBox; SetUserInput(textBox, true); } // Catches Backspace, Delete, Enter private static void textBox_PreviewKeyDown(object sender, KeyEventArgs e) { TextBox textBox = sender as TextBox; if (e.Key == Key.Return) { if (textBox.AcceptsReturn == true) { SetUserInput(textBox, true); } } else if (e.Key == Key.Delete) { if (textBox.SelectionLength &gt; 0 || textBox.SelectionStart &lt; textBox.Text.Length) { SetUserInput(textBox, true); } } else if (e.Key == Key.Back) { if (textBox.SelectionLength &gt; 0 || textBox.SelectionStart &gt; 0) { SetUserInput(textBox, true); } } } // Catches pasting private static void textBox_TextPasted(object sender, DataObjectPastingEventArgs e) { TextBox textBox = sender as TextBox; if (e.SourceDataObject.GetDataPresent(DataFormats.Text, true) == false) { return; } SetUserInput(textBox, true); } private static void textBox_TextChanged(object sender, TextChangedEventArgs e) { TextBox textBox = sender as TextBox; TextChangedFired(textBox, e); SetUserInput(textBox, false); } private static void TextChangedFired(TextBox sender, TextChangedEventArgs e) { ICommand command = (ICommand)sender.GetValue(TextChangedCommandProperty); object[] arguments = new object[] { sender, e, GetUserInput(sender) }; command.Execute(arguments); } #region UserInput private static DependencyProperty UserInputProperty = DependencyProperty.RegisterAttached("UserInput", typeof(bool), typeof(TextChangedBehavior)); private static void SetUserInput(DependencyObject target, bool value) { target.SetValue(UserInputProperty, value); } private static bool GetUserInput(DependencyObject target) { return (bool)target.GetValue(UserInputProperty); } #endregion // UserInput } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POTextBox TextChanged event on programmatic versus user change of text contents
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USFredrik Hedblad
    1. USFredrik Hedblad
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTBountyClose
    1. COYou also need to handle the cut (ctrl+x) command.
      singulars
      1. PO
      1. USbitbonk
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload