Richtextbox wpf 绑定

Question

要在 WPF RichtextBox 中对 Document 进行数据绑定，到目前为止我看到了 2 个解决方案，它们是从 RichtextBox 派生并添加 < code>DependencyProperty，以及带有“代理”的解决方案。

第一个和第二个都不令人满意。有人知道另一种解决方案，或者是一个能够数据绑定的商业 RTF 控件吗？普通的 TextBox 不是替代方案，因为我们需要文本格式。

有什么想法吗？

Answer 1

有一个更简单的方法！

您可以轻松创建附加的 DocumentXaml（或 DocumentRTF）属性，该属性允许您绑定 RichTextBox 的文档。它的使用方式如下，其中 Autobiography 是数据模型中的字符串属性：

<TextBox Text="{Binding FirstName}" />
<TextBox Text="{Binding LastName}" />
<RichTextBox local:RichTextBoxHelper.DocumentXaml="{Binding Autobiography}" />

瞧！完全可绑定 RichTextBox 数据！

该属性的实现非常简单：设置该属性后，将 XAML（或 RTF）加载到新的 FlowDocument 中。当FlowDocument更改时，更新属性值。

此代码应该可以解决问题：

using System.IO;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
public class RichTextBoxHelper : DependencyObject
{
    public static string GetDocumentXaml(DependencyObject obj)
    {
        return (string)obj.GetValue(DocumentXamlProperty);
    }

    public static void SetDocumentXaml(DependencyObject obj, string value)
    {
        obj.SetValue(DocumentXamlProperty, value);
    }

    public static readonly DependencyProperty DocumentXamlProperty =
        DependencyProperty.RegisterAttached(
            "DocumentXaml",
            typeof(string),
            typeof(RichTextBoxHelper),
            new FrameworkPropertyMetadata
            {
                BindsTwoWayByDefault = true,
                PropertyChangedCallback = (obj, e) =>
                {
                    var richTextBox = (RichTextBox)obj;

                    // Parse the XAML to a document (or use XamlReader.Parse())
                    var xaml = GetDocumentXaml(richTextBox);
                    var doc = new FlowDocument();
                    var range = new TextRange(doc.ContentStart, doc.ContentEnd);

                    range.Load(new MemoryStream(Encoding.UTF8.GetBytes(xaml)),
                          DataFormats.Xaml);

                    // Set the document
                    richTextBox.Document = doc;

                    // When the document changes update the source
                    range.Changed += (obj2, e2) =>
                    {
                        if (richTextBox.Document == doc)
                        {
                            MemoryStream buffer = new MemoryStream();
                            range.Save(buffer, DataFormats.Xaml);
                            SetDocumentXaml(richTextBox,
                                Encoding.UTF8.GetString(buffer.ToArray()));
                        }
                    };
                }
            });
}

相同的代码可用于 TextFormats.RTF 或 TextFormats.XamlPackage。对于 XamlPackage，您将拥有 byte[] 类型的属性，而不是 string。

与普通 XAML 相比，XamlPackage 格式具有多个优点，特别是能够包含图像等资源，并且比 RTF 更灵活且更易于使用。

很难相信这个问题已经搁置了 15 个月，却没有人指出解决这个问题的简单方法。

Answer 2

我知道这是一篇旧帖子，但请查看扩展 WPF 工具包。它有一个 RichTextBox 支持您尝试执行的操作。

Answer 3

我对之前的代码做了一些调整。
首先 range.Changed 对我不起作用。
在我将 range.Changed 更改为 richTextBox.TextChanged 后，事实证明 TextChanged 事件处理程序可以递归调用 SetDocumentXaml，因此我提供了针对它的保护。我还使用 XamlReader/XamlWriter 而不是 TextRange。

public class RichTextBoxHelper : DependencyObject
{
    private static HashSet<Thread> _recursionProtection = new HashSet<Thread>();

    public static string GetDocumentXaml(DependencyObject obj)
    {
        return (string)obj.GetValue(DocumentXamlProperty);
    }

    public static void SetDocumentXaml(DependencyObject obj, string value)
    {
        _recursionProtection.Add(Thread.CurrentThread);
        obj.SetValue(DocumentXamlProperty, value);
        _recursionProtection.Remove(Thread.CurrentThread);
    }

    public static readonly DependencyProperty DocumentXamlProperty = DependencyProperty.RegisterAttached(
        "DocumentXaml", 
        typeof(string), 
        typeof(RichTextBoxHelper), 
        new FrameworkPropertyMetadata(
            "", 
            FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.BindsTwoWayByDefault,
            (obj, e) => {
                if (_recursionProtection.Contains(Thread.CurrentThread))
                    return;

                var richTextBox = (RichTextBox)obj;

                // Parse the XAML to a document (or use XamlReader.Parse())

                try
                {
                    var stream = new MemoryStream(Encoding.UTF8.GetBytes(GetDocumentXaml(richTextBox)));
                    var doc = (FlowDocument)XamlReader.Load(stream);

                    // Set the document
                    richTextBox.Document = doc;
                }
                catch (Exception)
                {
                    richTextBox.Document = new FlowDocument();
                }

                // When the document changes update the source
                richTextBox.TextChanged += (obj2, e2) =>
                {
                    RichTextBox richTextBox2 = obj2 as RichTextBox;
                    if (richTextBox2 != null)
                    {
                        SetDocumentXaml(richTextBox, XamlWriter.Save(richTextBox2.Document));
                    }
                };
            }
        )
    );
}

Answer 4

我可以给你一个不错的解决方案，你可以接受它，但在我这样做之前，我将尝试解释为什么 Document 不是 DependencyProperty。

在 RichTextBox 控件的生命周期内，Document 属性通常不会更改。 RichTextBox 使用 FlowDocument 进行初始化。该文档已显示，可以通过多种方式进行编辑和修改，但 Document 属性的基础值仍然是 FlowDocument 的一个实例。因此，实际上没有理由它应该是一个 DependencyProperty，即 Bindable。如果您有多个位置引用此 FlowDocument，则只需引用一次。由于到处都是相同的实例，因此每个人都可以访问这些更改。

我认为 FlowDocument 不支持文档更改通知，尽管我不确定。

话虽这么说，这是一个解决方案。在开始之前，由于 RichTextBox 未实现 INotifyPropertyChanged 并且 Document 不是 DependencyProperty，因此当 RichTextBox< /code> 的 Document 属性发生变化，因此绑定只能是 OneWay。

创建一个提供 FlowDocument 的类。绑定需要存在 DependencyProperty，因此此类继承自 DependencyObject。

class HasDocument : DependencyObject
{
    public static readonly DependencyProperty DocumentProperty =
        DependencyProperty.Register("Document", 
                                    typeof(FlowDocument), 
                                    typeof(HasDocument), 
                                    new PropertyMetadata(new PropertyChangedCallback(DocumentChanged)));

    private static void DocumentChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e)
    {
        Debug.WriteLine("Document has changed");
    }

    public FlowDocument Document
    {
        get { return GetValue(DocumentProperty) as FlowDocument; }
        set { SetValue(DocumentProperty, value); }
    }
}

使用 XAML 创建一个带有富文本框的 Window。

<Window x:Class="samples.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Flow Document Binding" Height="300" Width="300"
    >
    <Grid>
      <RichTextBox Name="richTextBox" />
    </Grid>
</Window>

为 Window 提供一个 HasDocument 类型的字段。

HasDocument hasDocument;

窗口构造函数应该创建绑定。

hasDocument = new HasDocument();

InitializeComponent();

Binding b = new Binding("Document");
b.Source = richTextBox;
b.Mode = BindingMode.OneWay;
BindingOperations.SetBinding(hasDocument, HasDocument.DocumentProperty, b);

如果您希望能够在 XAML 中声明绑定，则必须使 HasDocument 类从 FrameworkElement 派生，以便可以将其插入到逻辑树中。

现在，如果您要更改 HasDocument 上的 Document 属性，富文本框的 Document 也会更改。

FlowDocument d = new FlowDocument();
Paragraph g = new Paragraph();
Run a = new Run();
a.Text = "I showed this using a binding";
g.Inlines.Add(a);
d.Blocks.Add(g);

hasDocument.Document = d;

Answer 5

 <RichTextBox>
     <FlowDocument PageHeight="180">
         <Paragraph>
             <Run Text="{Binding Text, Mode=TwoWay}"/>
          </Paragraph>
     </FlowDocument>
 </RichTextBox>

这似乎是迄今为止最简单的方法，并且没有显示在任何这些答案中。

在视图模型中只有 Text 变量。

Answer 6

创建一个 UserControl，其中有一个名为 RTB 的 RichTextBox。现在添加以下依赖属性：

    public FlowDocument Document
    {
        get { return (FlowDocument)GetValue(DocumentProperty); }
        set { SetValue(DocumentProperty, value); }
    }

    public static readonly DependencyProperty DocumentProperty =
        DependencyProperty.Register("Document", typeof(FlowDocument), typeof(RichTextBoxControl), new PropertyMetadata(OnDocumentChanged));

    private static void OnDocumentChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        RichTextBoxControl control = (RichTextBoxControl) d;
        FlowDocument document = e.NewValue as FlowDocument;
        if (document  == null)
        {
            control.RTB.Document = new FlowDocument(); //Document is not amused by null :)
        }
        else
        {
            control.RTB.Document = document;
        }
    }

此解决方案可能是您在某处看到的“代理”解决方案..但是.. RichTextBox 根本没有 Document 作为 DependencyProperty... 所以您必须以另一种方式执行此操作...

HTH

Answer 7

https://stackoverflow.com/a/2989277/3001007的答案满足了我的大部分需求="https://stackoverflow.com/users/360374/krzysztof">krzysztof。但该代码的一个问题（我面临的是），绑定不适用于多个控件。因此，我使用基于 Guid 的实现更改了 _recursionProtection。所以它也适用于同一窗口中的多个控件。

 public class RichTextBoxHelper : DependencyObject
    {
        private static List<Guid> _recursionProtection = new List<Guid>();

        public static string GetDocumentXaml(DependencyObject obj)
        {
            return (string)obj.GetValue(DocumentXamlProperty);
        }

        public static void SetDocumentXaml(DependencyObject obj, string value)
        {
            var fw1 = (FrameworkElement)obj;
            if (fw1.Tag == null || (Guid)fw1.Tag == Guid.Empty)
                fw1.Tag = Guid.NewGuid();
            _recursionProtection.Add((Guid)fw1.Tag);
            obj.SetValue(DocumentXamlProperty, value);
            _recursionProtection.Remove((Guid)fw1.Tag);
        }

        public static readonly DependencyProperty DocumentXamlProperty = DependencyProperty.RegisterAttached(
            "DocumentXaml",
            typeof(string),
            typeof(RichTextBoxHelper),
            new FrameworkPropertyMetadata(
                "",
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.BindsTwoWayByDefault,
                (obj, e) =>
                {
                    var richTextBox = (RichTextBox)obj;
                    if (richTextBox.Tag != null && _recursionProtection.Contains((Guid)richTextBox.Tag))
                        return;


                    // Parse the XAML to a document (or use XamlReader.Parse())

                    try
                    {
                        string docXaml = GetDocumentXaml(richTextBox);
                        var stream = new MemoryStream(Encoding.UTF8.GetBytes(docXaml));
                        FlowDocument doc;
                        if (!string.IsNullOrEmpty(docXaml))
                        {
                            doc = (FlowDocument)XamlReader.Load(stream);
                        }
                        else
                        {
                            doc = new FlowDocument();
                        }

                        // Set the document
                        richTextBox.Document = doc;
                    }
                    catch (Exception)
                    {
                        richTextBox.Document = new FlowDocument();
                    }

                    // When the document changes update the source
                    richTextBox.TextChanged += (obj2, e2) =>
                        {
                            RichTextBox richTextBox2 = obj2 as RichTextBox;
                            if (richTextBox2 != null)
                            {
                                SetDocumentXaml(richTextBox, XamlWriter.Save(richTextBox2.Document));
                            }
                        };
                }
            )
        );
    }

为了完整起见，让我在原始答案中添加几行 https://stackoverflow.com/a/2641774/3001007作者：ray-burns。这就是如何使用助手。

<RichTextBox local:RichTextBoxHelper.DocumentXaml="{Binding Autobiography}" />

Answer 8

这是我的解决方案，基于 Ray Burns 的答案，使用 DataBinding 并将 XAML 字符串转换为 RichTextBox 文档：

ViewModel

    TestText = @"<FlowDocument xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation""><Paragraph><Bold>Hello World!</Bold></Paragraph></FlowDocument>";

View

<RichTextBox local:RichTextBoxHelper.DocumentXaml="{Binding TestText}"/>

RichTextBoxHelper

public class RichTextBoxHelper : DependencyObject
{
    public static string GetDocumentXaml(DependencyObject obj) { return (string) obj.GetValue(DocumentXamlProperty); }

    public static void SetDocumentXaml(DependencyObject obj,
                                       string value)
    {
        obj.SetValue(DocumentXamlProperty, value);
    }

    public static readonly DependencyProperty DocumentXamlProperty = DependencyProperty.RegisterAttached
    (
        "DocumentXaml",
        typeof(string),
        typeof(RichTextBoxHelper),
        new FrameworkPropertyMetadata
        {
            BindsTwoWayByDefault = true,
            PropertyChangedCallback = (obj,
                                       e) =>
            {
                var    richTextBox = (RichTextBox) obj;
                var    xaml        = GetDocumentXaml(richTextBox);
                Stream sm          = new MemoryStream(Encoding.UTF8.GetBytes(xaml));
                richTextBox.Document = (FlowDocument) XamlReader.Load(sm);
                sm.Close();
            }
        }
    );
}

Answer 9

这是 Lolo 答案的 VB.Net 版本：

Public Class RichTextBoxHelper
Inherits DependencyObject

Private Shared _recursionProtection As New HashSet(Of System.Threading.Thread)()

Public Shared Function GetDocumentXaml(ByVal depObj As DependencyObject) As String
    Return DirectCast(depObj.GetValue(DocumentXamlProperty), String)
End Function

Public Shared Sub SetDocumentXaml(ByVal depObj As DependencyObject, ByVal value As String)
    _recursionProtection.Add(System.Threading.Thread.CurrentThread)
    depObj.SetValue(DocumentXamlProperty, value)
    _recursionProtection.Remove(System.Threading.Thread.CurrentThread)
End Sub

Public Shared ReadOnly DocumentXamlProperty As DependencyProperty = DependencyProperty.RegisterAttached("DocumentXaml", GetType(String), GetType(RichTextBoxHelper), New FrameworkPropertyMetadata("", FrameworkPropertyMetadataOptions.AffectsRender Or FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, Sub(depObj, e)
                                                                                                                                                                                                                                                                                                                    RegisterIt(depObj, e)
                                                                                                                                                                                                                                                                                                                End Sub))

Private Shared Sub RegisterIt(ByVal depObj As System.Windows.DependencyObject, ByVal e As System.Windows.DependencyPropertyChangedEventArgs)
    If _recursionProtection.Contains(System.Threading.Thread.CurrentThread) Then
        Return
    End If
    Dim rtb As RichTextBox = DirectCast(depObj, RichTextBox)
    Try
        rtb.Document = Markup.XamlReader.Parse(GetDocumentXaml(rtb))
    Catch
        rtb.Document = New FlowDocument()
    End Try
    ' When the document changes update the source
    AddHandler rtb.TextChanged, AddressOf TextChanged
End Sub

Private Shared Sub TextChanged(ByVal sender As Object, ByVal e As TextChangedEventArgs)
    Dim rtb As RichTextBox = TryCast(sender, RichTextBox)
    If rtb IsNot Nothing Then
        SetDocumentXaml(sender, Markup.XamlWriter.Save(rtb.Document))
    End If
End Sub

End Class

Answer 10

这个 VB.Net 版本适合我的情况。我删除了线程集合信号量，而是使用RemoveHandler 和AddHandler。另外，由于 FlowDocument 一次只能绑定到一个 RichTextBox，因此我检查了 RichTextBox 的 IsLoaded=True。让我们从我如何在 MVVM 应用程序中使用该类开始，该应用程序使用 ResourceDictionary 而不是 Window。

    ' Loaded and Unloaded events seems to be the only way to initialize a control created from a Resource Dictionary
' Loading document here because Loaded is the last available event to create a document
Private Sub Rtb_Loaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
    ' only good place to initialize RichTextBox.Document with DependencyProperty
    Dim rtb As RichTextBox = DirectCast(sender, RichTextBox)
    Try
        rtb.Document = RichTextBoxHelper.GetDocumentXaml(rtb)
    Catch ex As Exception
        Debug.WriteLine("Rtb_Loaded: Message:" & ex.Message)
    End Try
End Sub

' Loaded and Unloaded events seems to be the only way to initialize a control created from a Resource Dictionary
' Free document being held by RichTextBox.Document by assigning New FlowDocument to RichTextBox.Document. Otherwise we'll see an of "Document belongs to another RichTextBox"
Private Sub Rtb_Unloaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
    Dim rtb As RichTextBox = DirectCast(sender, RichTextBox)
    Dim fd As New FlowDocument
    RichTextBoxHelper.SetDocumentXaml(rtb, fd)
    Try
        rtb.Document = fd
    Catch ex As Exception
        Debug.WriteLine("PoemDocument.PoemDocumentView.PoemRtb_Unloaded: Message:" & ex.Message)
    End Try
End Sub

Public Class RichTextBoxHelper
    Inherits DependencyObject

    Public Shared Function GetDocumentXaml(ByVal depObj As DependencyObject) As FlowDocument
        Return depObj.GetValue(DocumentXamlProperty)
    End Function

    Public Shared Sub SetDocumentXaml(ByVal depObj As DependencyObject, ByVal value As FlowDocument)
        depObj.SetValue(DocumentXamlProperty, value)
    End Sub

    Public Shared ReadOnly DocumentXamlProperty As DependencyProperty = DependencyProperty.RegisterAttached("DocumentXaml", GetType(FlowDocument), GetType(RichTextBoxHelper), New FrameworkPropertyMetadata(Nothing, FrameworkPropertyMetadataOptions.AffectsRender Or FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, Sub(depObj, e)
                                                                                                                                                                                                                                                                                                                                   RegisterIt(depObj, e)
                                                                                                                                                                                                                                                                                                                               End Sub))


    Private Shared Sub RegisterIt(ByVal depObj As System.Windows.DependencyObject, ByVal e As System.Windows.DependencyPropertyChangedEventArgs)
        Dim rtb As RichTextBox = DirectCast(depObj, RichTextBox)
        If rtb.IsLoaded Then
            RemoveHandler rtb.TextChanged, AddressOf TextChanged
            Try
                rtb.Document = GetDocumentXaml(rtb)
            Catch ex As Exception
                Debug.WriteLine("RichTextBoxHelper.RegisterIt: ex:" & ex.Message)
                rtb.Document = New FlowDocument()
            End Try
            AddHandler rtb.TextChanged, AddressOf TextChanged
        Else
            Debug.WriteLine("RichTextBoxHelper: Unloaded control ignored:" & rtb.Name)
        End If
    End Sub

    ' When a RichTextBox Document changes, update the DependencyProperty so they're in sync.
    Private Shared Sub TextChanged(ByVal sender As Object, ByVal e As TextChangedEventArgs)
        Dim rtb As RichTextBox = TryCast(sender, RichTextBox)
        If rtb IsNot Nothing Then
            SetDocumentXaml(sender, rtb.Document)
        End If
    End Sub

End Class

Answer 11

伙计们，为什么要为所有这些事情烦恼呢？这非常有效。无需代码

<RichTextBox>
    <FlowDocument>
        <Paragraph>
            <Run Text="{Binding Mytextbinding}"/>
        </Paragraph>
    </FlowDocument>
</RichTextBox>