Question

我在WPF中创建了一个用户控件：

<UserControl
x:Class="BARCIndia.Mobile.Views.UserControls.SubCategoryUserControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:BARCIndia.Mobile.Views.UserControls"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" 
d:DesignHeight="300"
d:DesignWidth="400">

  <Grid>
    <StackPanel Background="DarkCyan">                
     <TextBlock Name="txtName" FontSize="26"></TextBlock>
    </StackPanel>
  </Grid>        
</UserControl>

后面的代码有一个名为＆＃34; ParamValue＆＃34;它设置为我的用户控件TextBlock:txtName

的文本

 public sealed partial class SubCategoryUserControl : UserControl
    {        
      public string ParamValue
      {
        get { return (string)GetValue(ParamValueProperty); }
        set { SetValue(ParamValueProperty, value); }
      }        
      public static readonly DependencyProperty ParamValueProperty =  DependencyProperty.Register
      (
       "ParamValue",
       typeof(string),
       typeof(SubCategoryUserControl),
       new PropertyMetadata(string.Empty)
      );

    public SubCategoryUserControl()
    {
    this.InitializeComponent();
    txtName.Text = this.ParamValue;
    }          
  }

从xaml表单调用

<Grid >

<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>

<Myusercontrol:SubCategoryUserControl x:Name="tempUserControl" ParamValue="From Window" Grid.Row="0"/>

</Grid>

这里我传递参数 ParamValue =＆＃34;来自Window＆＃34; 当usercontrol加载的文本块显示为空时。

属性未更新其显示的emtry字符串，即在创建依赖属性时分配的默认值

public static readonly DependencyProperty ParamValueProperty = DependencyProperty.Register
           (
                "ParamValue",
                typeof(string),
                typeof(SubCategoryUserControl),
                **new PropertyMetadata(string.Empty)**
           );

我如何获得指定值？

Answer 1

在您的情况下，它可能如下所示：

public sealed partial class SubCategoryUserControl : UserControl
{
    public string ParamValue
    {
        get
        {
            return (string) GetValue(ParamValueProperty);
        }
        set
        {
            SetValue(ParamValueProperty, value);
        }
    }

    public static readonly DependencyProperty ParamValueProperty = DependencyProperty.Register
        (
            "ParamValue",
            typeof (string),
            typeof (SubCategoryUserControl),
            new PropertyMetadata(string.Empty)
        );

    public SubCategoryUserControl()
    {
        this.InitializeComponent();
    }
}

和xaml：

<UserControl x:Class="BARCIndia.Mobile.Views.UserControls.SubCategoryUserControl"
             x:Name="Root"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="using:BARCIndia.Mobile.Views.UserControls"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             mc:Ignorable="d"
             d:DesignHeight="300"
             d:DesignWidth="400">

  <Grid>
    <StackPanel Background="DarkCyan">                
     <TextBlock Text="{Binding ParamValue, ElementName=Root}" FontSize="26" />
    </StackPanel>
  </Grid>        
</UserControl>

如何将参数传递给窗口手机中的usercontrol？

1 个答案: