如果我从GotFocus事件处理程序中调用SelectAll，它对鼠标不起作用——鼠标一释放，选择就消失了。
编辑:人们喜欢唐纳利的回答，我将试着解释为什么我不像公认的答案那样喜欢它。
It is more complex, while the accepted answer does the same thing in a simpler way.
The usability of accepted answer is better. When you click in the middle of the text, text gets unselected when you release the mouse allowing you to start editing instantly, and if you still want to select all, just press the button again and this time it will not unselect on release. Following Donelle's recipe, if I click in the middle of text, I have to click second time to be able to edit. If I click somewhere within the text versus outside of the text, this most probably means I want to start editing instead of overwriting everything.
我对此有一个稍微简化的答案(只有PreviewMouseLeftButtonDown事件)，这似乎模仿了浏览器的常用功能:
在XAML中，你有一个文本框说:
<TextBox Text="http://www.blabla.com" BorderThickness="2" BorderBrush="Green" VerticalAlignment="Center" Height="25"
PreviewMouseLeftButtonDown="SelectAll" />
在后台代码:
private void SelectAll(object sender, MouseButtonEventArgs e)
{
TextBox tb = (sender as TextBox);
if (tb == null)
{
return;
}
if (!tb.IsKeyboardFocusWithin)
{
tb.SelectAll();
e.Handled = true;
tb.Focus();
}
}
我也有同样的问题。在VB。Net的工作方式很简单:
VB
XAML:
<TextBox x:Name="txtFilterFrequency" />
Codehind:
Private Sub txtFilterText_GotFocus(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles txtFilterText.GotFocus
Me.Dispatcher.BeginInvoke(Sub()
txtFilterText.SelectAll()
End Sub, DispatcherPriority.ApplicationIdle, Nothing)
End Sub
c#(感谢ViRuSTriNiTy)
private delegate void TextBoxSelectAllDelegate(object sender);
private void TextBoxSelectAll(object sender)
{
(sender as System.Windows.Controls.TextBox).SelectAll();
}
private void MyTextBox_GotFocus(object sender, System.Windows.RoutedEventArgs e)
{
TextBoxSelectAllDelegate d = TextBoxSelectAll;
this.Dispatcher.BeginInvoke(d,
System.Windows.Threading.DispatcherPriority.ApplicationIdle, sender);
}
这个简单的实现非常适合我:
void TextBox_GotFocus(object sender, RoutedEventArgs e)
{
((TextBox) sender).SelectAll();
}
void TextBox_PreviewMouseDown(object sender, MouseButtonEventArgs e)
{
var TextBox = (TextBox) sender;
if (!TextBox.IsKeyboardFocusWithin)
{
TextBox.Focus();
e.Handled = true;
}
}
把它应用到所有的文本框，把下面的代码InitializeComponent();
EventManager.RegisterClassHandler(typeof(TextBox), TextBox.GotFocusEvent, new RoutedEventHandler(TextBox_GotFocus));
EventManager.RegisterClassHandler(typeof(TextBox), TextBox.PreviewMouseDownEvent, new MouseButtonEventHandler(TextBox_PreviewMouseDown));
我已经测试了所有的，但只有以下工作:
protected override void OnStartup(StartupEventArgs e)
{
EventManager.RegisterClassHandler(typeof(TextBox), UIElement.PreviewMouseLeftButtonDownEvent,
new MouseButtonEventHandler(SelectivelyHandleMouseButton), true);
EventManager.RegisterClassHandler(typeof(TextBox), UIElement.GotKeyboardFocusEvent,
new RoutedEventHandler(SelectAllText), true);
EventManager.RegisterClassHandler(typeof(TextBox), UIElement.GotFocusEvent,
new RoutedEventHandler(GotFocus), true);
}
private static void SelectivelyHandleMouseButton(object sender, MouseButtonEventArgs e)
{
var textbox = (sender as TextBox);
if (textbox != null)
{
int hc = textbox.GetHashCode();
if (hc == LastHashCode)
{
if (e.OriginalSource.GetType().Name == "TextBoxView")
{
e.Handled = true;
textbox.Focus();
LastHashCode = -1;
}
}
}
if (textbox != null) textbox.Focus();
}
private static void SelectAllText(object sender, RoutedEventArgs e)
{
var textBox = e.OriginalSource as TextBox;
if (textBox != null)
textBox.SelectAll();
}
private static int LastHashCode;
private static void GotFocus(object sender, RoutedEventArgs e)
{
var textBox = e.OriginalSource as TextBox;
if (textBox != null)
LastHashCode = textBox.GetHashCode();
}
这对我来说似乎很有效。它基本上是一些早期帖子的重述。我只是把它放到构造函数的MainWindow.xaml.cs文件中。我创建了两个处理程序，一个用于键盘，一个用于鼠标，并将两个事件导入同一个函数HandleGotFocusEvent，该函数定义在同一个文件的构造函数之后。
public MainWindow()
{
InitializeComponent();
EventManager.RegisterClassHandler(typeof(TextBox),
UIElement.GotKeyboardFocusEvent,
new RoutedEventHandler(HandleGotFocusEvent), true);
EventManager.RegisterClassHandler(typeof(TextBox),
UIElement.GotMouseCaptureEvent,
new RoutedEventHandler(HandleGotFocusEvent), true);
}
private void HandleGotFocusEvent(object sender, RoutedEventArgs e)
{
if (sender is TextBox)
(sender as TextBox).SelectAll();
}
