C# XAML自定义文本框事件和属性未实时更新
从C# XAML自定义文本框事件和属性未实时更新,c#,xaml,win-universal-app,uwp,uwp-xaml,C#,Xaml,Win Universal App,Uwp,Uwp Xaml,从TextBox继承并连接TextChanged事件后,订阅TextChanged事件时,Text属性不准确 这是我的控制: [TemplatePart(Name = "PART_ctlTextBox", Type = typeof(TextBox))] public class CustomTextBox : Control { public CustomTextBox() { DefaultStyleKey = typeof(CustomTextBox);
TextBox
继承并连接TextChanged事件后,订阅TextChanged事件时,Text属性不准确
这是我的控制:
[TemplatePart(Name = "PART_ctlTextBox", Type = typeof(TextBox))]
public class CustomTextBox : Control
{
public CustomTextBox()
{
DefaultStyleKey = typeof(CustomTextBox);
}
protected override void OnApplyTemplate()
{
base.OnApplyTemplate();
var textBox = GetTemplateChild("PART_ctlTextBox") as TextBox;
if (textBox != null)
{
textBox.TextChanged += (s, a) => TextChanged?.Invoke(s, a);
}
}
public event TextChangedEventHandler TextChanged;
public string Text
{
get { return (string)GetValue(TextProperty); }
set { SetValue(TextProperty, value); }
}
public static readonly DependencyProperty TextProperty = DependencyProperty.Register("Text", typeof(string), typeof(CustomTextBox), new PropertyMetadata(null));
}
以下是通用XAML:
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:customControls="using:CustomControls">
<Style TargetType="customControls:CustomTextBox">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="customControls:CustomTextBox">
<TextBox x:Name="PART_ctlTextBox" Text="{Binding RelativeSource={RelativeSource TemplatedParent}, Mode=TwoWay, Path=Text, UpdateSourceTrigger=PropertyChanged}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>
请注意,常规的
TextBox
会实时更新,而CustomTextBox
会延迟。我也尝试过用操作点击TextChanged。调用没有效果。你所说的“常规文本框实时更新,而CustomTextBox延迟”是什么意思?我看不出有什么不同。与常规文本框相比,CustomTextBox
的文本块标签更新似乎延迟了1个字符。例如,如果我在两个文本框中键入“123”,则lblRegularTextBox
将显示“123”,但lblCustomTextBox
将仅显示“12”。您所说的“常规文本框实时更新,而自定义文本框延迟”是什么意思?我看不出有什么不同。与常规文本框相比,CustomTextBox
的文本块标签更新似乎延迟了1个字符。例如,如果我在两个文本框中都键入“123”,则lblRegularTextBox
将显示“123”,但lblCustomTextBox
将仅显示“12”
<Grid>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<TextBlock x:Name="lblCustomTextBox" Grid.Row="0" VerticalAlignment="Bottom" />
<local:CustomTextBox Grid.Row="1" x:Name="txtCustomTextBox" TextChanged="customTextBox_OnTextChanged" />
<TextBlock x:Name="lblRegularTextBox" Grid.Row="2" VerticalAlignment="Bottom" />
<TextBox x:Name="txtRegularTextBox" Grid.Row="3" TextChanged="regularTextBox_OnTextChanged"></TextBox>
</Grid>
private void customTextBox_OnTextChanged(object sender, TextChangedEventArgs e)
{
lblCustomTextBox.Text = txtCustomTextBox.Text ?? string.Empty;
}
private void regularTextBox_OnTextChanged(object sender, TextChangedEventArgs e)
{
lblRegularTextBox.Text = txtRegularTextBox.Text ?? string.Empty;
}