这里是一些代码(viewmodels使用某种mvvm框架,在ViewModelBase类中实现INotifyPropertyChanged,但希望没问题)：

MainWindow.xaml：

<Window x:Class="DPandMVVM.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:DPandMVVM"
    Title="MainWindow" Height="300" Width="300">
        <local:UserControl1 TextInControl="{Binding Text}" />
    </Grid>
</Window>

CodeBehind MainWindow.xaml.cs：

using System.Windows;
namespace DPandMVVM
    public partial class MainWindow : Window
        public MainWindow()
            InitializeComponent();
            DataContext = new MainWindowVM();
MainWindow-ViewModel MainWindowVM.cs：
namespace DPandMVVM
    public class MainWindowVM : ViewModelBase
        private string _text;
        public string Text { get { return _text; } }
        public MainWindowVM()
            _text = "Text from MainWindowVM";
在这里UserControl1.xaml：
<UserControl x:Class="DPandMVVM.UserControl1"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
        <TextBlock Text="{Binding TextInTextBlock}" />  
    </Grid>
</UserControl>
Codebehind UserControl1.xaml.cs：
using System.Windows.Controls;    
namespace DPandMVVM
    /// <summary>
    /// Interaction logic for UserControl1.xaml
    /// </summary>
    public partial class UserControl1 : UserControl
        public UserControl1()
            InitializeComponent();
            DataContext = new UserControl1VM();
和Viewmodel UserControl1VM.cs：
using System.Windows;    
namespace DPandMVVM
    public class UserControl1VM : DependencyObject
        public UserControl1VM()
            TextInControl = "TextfromUserControl1VM";
        public string TextInControl
            get { return (string)GetValue(TextInControlProperty); }
            set { SetValue(TextInControlProperty, value); }
        public static readonly DependencyProperty TextInControlProperty =
            DependencyProperty.Register("TextInControl", typeof(string), typeof(UserControl1VM));
使用此星座,无法在MainWindow.xaml中找到DP. 我究竟做错了什么？
首先,如果要从外部绑定它,则需要在UserControl1中声明DependencyProperty TextInControl.
在UserControl1中移动DP的声明.
public partial class UserControl1 : UserControl
    public UserControl1()
        InitializeComponent();
    public string TextInControl
        get { return (string)GetValue(TextInControlProperty); }
        set { SetValue(TextInControlProperty, value); }
    public static readonly DependencyProperty TextInControlProperty =
        DependencyProperty.Register("TextInControl", typeof(string), 
                                       typeof(UserControl1));
其次,你将UserControl的DataContext外部设置为UserControl1VM,
public UserControl1()
        InitializeComponent();
        DataContext = new UserControl1VM(); <-- HERE (Remove this)
所以WPF绑定引擎在UserControl1VM中寻找属性Text而不是MainWindowVM.删除设置DataContext并将UserControl1的XAML更新为：
<UserControl x:Class="DPandMVVM.UserControl1"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300"
             x:Name="userControl1">
        <TextBlock Text="{Binding TextInTextBlock, ElementName=userControl1}" />  
    </Grid>
</UserControl>
通过在UserControl上设置x：Name,使用ElementName绑定DP.
UPDATE
如果您希望UserControl的ViewModel完好无损,则必须更新MainWindow中的绑定.
显式告诉WPF绑定引擎在MainWindow的DataContext中使用ElementName查找属性,如下所示：
<local:UserControl1 TextInControl="{Binding DataContext.Text,
                    ElementName=mainWindow}" />
为此,您需要在窗口根级别设置x：Name =“mainWindow”.
出处：http://www.voidcn.com/article/p-udpyjbsd-bue.html
注意： 在使用MVVM框架的时候，如果在vm里获取UserControl的绑定数据，需要使用双向绑定"{Binding PageIndex,Mode=TwoWay}"
======================================================================
另外在提供一个在界面上使用ContentControl控件来绑定UserControl对象的方法。
界面元素：
    <Window.DataContext>
        <localVM:BarViewModel />
    </Window.DataContext>
        <StackPanel Height="30" Margin="0,300,2,105">
            <ContentControl Content="{Binding StatusBar}"></ContentControl>
        </StackPanel>
    </Grid>
对应的BarViewModel类：
    public class BarViewMod : INotifyPropertyChanged
        public BarViewMod()
            StatusBar = new View.UserCtrl.StatusBarView();
        public object StatusBar { get; set; }
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName]string propertyName = "")
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
StatusBarView对于界面元素
<UserControl x:Class="WpfApp1.View.UserCtrl.StatusBarView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfApp1.View.UserCtrl"
             xmlns:uc="clr-namespace:WpfApp1.VM"
             mc:Ignorable="d" 
             d:DesignHeight="25" d:DesignWidth="800">
    <UserControl.DataContext>
        <uc:StatusBarViewModel></uc:StatusBarViewModel>
    </UserControl.DataContext>
        <StatusBar x:Name="MyStatusBar">
            <StatusBar.ItemsPanel>
                <ItemsPanelTemplate>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="100" />
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="100" />
                        </Grid.ColumnDefinitions>
                    </Grid>
                </ItemsPanelTemplate>
            </StatusBar.ItemsPanel>
            <StatusBarItem>
                <TextBlock Name="lbMsg" Text="{Binding TestMsg}" />
            </StatusBarItem>
            <Separator Grid.Column="1" />
            <StatusBarItem Grid.Column="2">
                <TextBlock Text="http://www.baidu.com/file.txt" />
            </StatusBarItem>
            <Separator Grid.Column="3" />
            <StatusBarItem Grid.Column="4">
                <ProgressBar Value="0" Width="90" Height="16" />
            </StatusBarItem>
        </StatusBar>
    </Grid>
</UserControl>
StatusBarView对应的ViewModel类：
namespace WpfApp1.VM
    using System.ComponentModel;
    using System.Runtime.CompilerServices;
    using System.Windows;
    public class StatusBarViewModel : INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName]string propertyName = "")
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        public string TestMsg { get; set; } = "test....";
 如果是使用了其他框架的，可以依照框架修改，如下面是使用了IOC框架的，则在主界面的VM中构造函数中创建UserControl对象：
StatusBar = _serviceProvider.GetRequiredService<UserCtrl.StatusBarViewModel>();