Question

wpf中，如何让textbox获得焦点时,其text被选中？

Answer 1

你写个附加属性，然后就可以在Style里面用了。
public class TextBoxHelper
{
public static readonly DependencyProperty AutoSelectAllProperty =
DependencyProperty.RegisterAttached("AutoSelectAll", typeof(bool), typeof(TextBoxHelper),
new FrameworkPropertyMetadata((bool)false,
new PropertyChangedCallback(OnAutoSelectAllChanged)));

public static bool GetAutoSelectAll(TextBoxBase d)
{
return (bool)d.GetValue(AutoSelectAllProperty);
}

public static void SetAutoSelectAll(TextBoxBase d, bool value)
{
d.SetValue(AutoSelectAllProperty, value);
}

private static void OnAutoSelectAllChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var textBox = d as TextBoxBase;
if (textBox != null)
{
var flag = (bool)e.NewValue;
if (flag)
{
textBox.GotFocus += TextBoxOnGotFocus;
}
else
{
textBox.GotFocus -= TextBoxOnGotFocus;
}
}
}

private static void TextBoxOnGotFocus(object sender, RoutedEventArgs e)
{
var textBox = sender as TextBoxBase;
if (textBox != null)
{
textBox.SelectAll();
}
}
}

然后在Style里面
<Setter Property="local:TextBoxHelper.AutoSelectAll" Value="True"/>

local是你引用的命名空间