要在 WPF RichtextBox 中对 Document 进行 DataBinding，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 DependencyProperty，以及带有“代理”的解决方案.
第一个或第二个都不令人满意。有人知道另一种解决方案，或者是能够DataBinding 的商业RTF 控件吗？普通的TextBox 不是替代品，因为我们需要文本格式。
有什么想法吗？
【问题讨论】：
标签： c# wpf data-binding richtextbox
创建一个包含名为 RTB 的 RichTextBox 的 UserControl。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 as DependencyProperty...所以您必须以另一种方式执行此操作...
HTH
【讨论】：
我可以给你一个好的解决方案，你可以接受它，但在我这样做之前，我将尝试解释为什么 Document 不是首先是 DependencyProperty。
在RichTextBox 控件的生命周期内，Document 属性通常不会改变。 RichTextBox 用 FlowDocument 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，它确实没有理由应该是DependencyProperty，即Bindable。如果您有多个位置引用此 FlowDocument，则只需引用一次。由于它在任何地方都是相同的实例，因此每个人都可以访问更改。
我不认为FlowDocument 支持文档更改通知，虽然我不确定。
话虽如此，这里有一个解决方案。在开始之前，由于RichTextBox 没有实现INotifyPropertyChanged 并且Document 不是DependencyProperty，所以当RichTextBox 的Document 属性发生变化时我们没有通知，因此绑定只能是OneWay。
创建一个将提供FlowDocument 的类。绑定需要DependencyProperty的存在，所以这个类继承自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 中的富文本框创建 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>
给Window 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，则必须使您的 HasDocument 类派生自 FrameworkElement，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;
【讨论】：
有一个更简单的方法！
您可以轻松创建附加的DocumentXaml（或DocumentRTF）属性，该属性将允许您绑定RichTextBox 的文档。它是这样使用的，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！
此属性的实现非常简单：设置属性后，将 XAML（或 RTF）加载到新的 FlowDocument 中。当FlowDocument 发生变化时，更新属性值。
这段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 格式有几个优点，尤其是能够包含图像等资源，而且它比 RTF 更灵活、更易于使用。
很难相信这个问题持续了 15 个月，没有人指出简单的方法。
【讨论】：
range.Changed 事件永远不会被调用。
我已经稍微调整了之前的代码。 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。我还使用了 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));
}
};
}
)
);
}
【讨论】：
<FlowDocument xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"><Paragraph Foreground="Red"><Bold>Hello</Bold></Paragraph></FlowDocument>
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
结束类
【讨论】：
这个 VB.Net 版本适用于我的情况。我删除了线程集合信号量，而不是使用 RemoveHandler 和 AddHandler。此外，由于 FlowDocument 一次只能绑定到一个 RichTextBox，因此我检查了 RichTextBox 的 IsLoaded=True。让我们从我如何在使用 ResourceDictionary 而不是 Window 的 MVVM 应用程序中使用该类开始。
' 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
【讨论】：
我知道这是一篇旧帖子，但请查看Extended WPF Toolkit。它有一个 RichTextBox 支持你正在尝试做的事情。
【讨论】：
伙计们，为什么要打扰所有的废话。这完美地工作。无需代码
<RichTextBox>
<FlowDocument>
<Paragraph>
<Run Text="{Binding Mytextbinding}"/>
</Paragraph>
</FlowDocument>
</RichTextBox>
【讨论】：
Text Run 的属性不是依赖属性，因此它甚至无法编译。只有依赖属性支持这样的绑定。
<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。
【讨论】：
https://stackoverflow.com/a/2989277/3001007krzysztof 的这个回答满足了我的大部分需求。但是该代码的一个问题（我面临的是），绑定不适用于多个控件。所以我用基于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，让我从ray-burns 的原始答案https://stackoverflow.com/a/2641774/3001007 中再添加几行。这是帮助程序的使用方法。
<RichTextBox local:RichTextBoxHelper.DocumentXaml="{Binding Autobiography}" />
【讨论】：
这是我的解决方案，基于 Ray Burns 的 DataBinding 答案并将 XAML 字符串转换为 RichTextBox-Document：
视图模型
TestText = @"<FlowDocument xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation""><Paragraph><Bold>Hello World!</Bold></Paragraph></FlowDocument>";
查看
<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();
}
}
);
}
【讨论】：