如何：使用上下文菜单中的拼写检查功能
默认情况下，在编辑控件（如 TextBox 或 RichTextBox）中启用拼写检查功能后，可在上下文菜单中获取拼写检查选项。 例如，当用户右键单击拼写错误的单词时，他们会收到一组拼写建议或“全部忽略”选项。 但是，使用自己的自定义上下文菜单替代默认上下文菜单时，此功能将丢失，并且需要编写代码才可在上下文菜单中重新启用拼写检查功能。 以下示例演示如何在 TextBox 上启用此功能。
定义上下文菜单
以下示例演示创建了一个 TextBox 的 Extensible Application Markup Language (XAML)，其中包含一些用于实现上下文菜单的事件。
<Page x:Class="SDKSample.SpellerCustomContextMenu"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Loaded="OnWindowLoaded">
<TextBox
Name="myTextBox"
TextWrapping="Wrap"
SpellCheck.IsEnabled="True"
ContextMenuOpening="tb_ContextMenuOpening">
In a custum menu you need to write code to add speler choices
because everything in a custom context menu has to be added explicitly.
</TextBox>
</Page>
实现上下文菜单
以下示例演示实现上下文菜单的代码。
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
namespace SDKSample
{
public partial class SpellerCustomContextMenu : Page
{
void OnWindowLoaded(object sender, RoutedEventArgs e)
{
//This is required for the first time ContextMenu invocation so that TextEditor doesnt handle it.
myTextBox.ContextMenu = GetContextMenu();
}
void tb_ContextMenuOpening(object sender, RoutedEventArgs e)
{
int caretIndex, cmdIndex;
SpellingError spellingError;
myTextBox.ContextMenu = GetContextMenu();
caretIndex = myTextBox.CaretIndex;
cmdIndex = 0;
spellingError = myTextBox.GetSpellingError(caretIndex);
if (spellingError != null)
{
foreach (string str in spellingError.Suggestions)
{
MenuItem mi = new MenuItem();
mi.Header = str;
mi.FontWeight = FontWeights.Bold;
mi.Command = EditingCommands.CorrectSpellingError;
mi.CommandParameter = str;
mi.CommandTarget = myTextBox;
myTextBox.ContextMenu.Items.Insert(cmdIndex, mi);
cmdIndex++;
}
Separator separatorMenuItem1 = new Separator();
myTextBox.ContextMenu.Items.Insert(cmdIndex, separatorMenuItem1);
cmdIndex++;
MenuItem ignoreAllMI = new MenuItem();
ignoreAllMI.Header = "Ignore All";
ignoreAllMI.Command = EditingCommands.IgnoreSpellingError;
ignoreAllMI.CommandTarget = myTextBox;
myTextBox.ContextMenu.Items.Insert(cmdIndex, ignoreAllMI);
cmdIndex++;
Separator separatorMenuItem2 = new Separator();
myTextBox.ContextMenu.Items.Insert(cmdIndex, separatorMenuItem2);
}
}
// Gets a fresh context menu.
private ContextMenu GetContextMenu()
{
ContextMenu cm = new ContextMenu();
//Can create STATIC custom menu items if exists here...
MenuItem m1, m2, m3, m4;
m1 = new MenuItem();
m1.Header = "File";
m2 = new MenuItem();
m2.Header = "Save";
m3 = new MenuItem();
m3.Header = "SaveAs";
m4 = new MenuItem();
m4.Header = "Recent Files";
//Can add functionality for the custom menu items here...
cm.Items.Add(m1);
cm.Items.Add(m2);
cm.Items.Add(m3);
cm.Items.Add(m4);
return cm;
}
}
}
Namespace SDKSample
Partial Public Class SpellerCustomContextMenu
Inherits Page
Private Sub OnWindowLoaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
'This is required for the first time ContextMenu invocation
'so that TextEditor doesnt handle it.
myTextBox.ContextMenu = GetContextMenu()
End Sub
Private Sub tb_ContextMenuOpening(ByVal sender As Object,
ByVal e As RoutedEventArgs)
Dim caretIndex, cmdIndex As Integer
Dim spellingError As SpellingError
myTextBox.ContextMenu = GetContextMenu()
caretIndex = myTextBox.CaretIndex
cmdIndex = 0
spellingError = myTextBox.GetSpellingError(caretIndex)
If spellingError IsNot Nothing Then
For Each str As String In spellingError.Suggestions
Dim mi As New MenuItem()
mi.Header = str
mi.FontWeight = FontWeights.Bold
mi.Command = EditingCommands.CorrectSpellingError
mi.CommandParameter = str
mi.CommandTarget = myTextBox
myTextBox.ContextMenu.Items.Insert(cmdIndex, mi)
cmdIndex += 1
Next str
Dim separatorMenuItem1 As New Separator()
myTextBox.ContextMenu.Items.Insert(cmdIndex, separatorMenuItem1)
cmdIndex += 1
Dim ignoreAllMI As New MenuItem()
ignoreAllMI.Header = "Ignore All"
ignoreAllMI.Command = EditingCommands.IgnoreSpellingError
ignoreAllMI.CommandTarget = myTextBox
myTextBox.ContextMenu.Items.Insert(cmdIndex, ignoreAllMI)
cmdIndex += 1
Dim separatorMenuItem2 As New Separator()
myTextBox.ContextMenu.Items.Insert(cmdIndex, separatorMenuItem2)
End If
End Sub
' Gets a fresh context menu.
Private Function GetContextMenu() As ContextMenu
Dim cm As New ContextMenu()
'Can create STATIC custom menu items if exists here...
Dim m1, m2, m3, m4 As MenuItem
m1 = New MenuItem()
m1.Header = "File"
m2 = New MenuItem()
m2.Header = "Save"
m3 = New MenuItem()
m3.Header = "SaveAs"
m4 = New MenuItem()
m4.Header = "Recent Files"
'Can add functionality for the custom menu items here...
cm.Items.Add(m1)
cm.Items.Add(m2)
cm.Items.Add(m3)
cm.Items.Add(m4)
Return cm
End Function
End Class
End Namespace
使用 RichTextBox 执行此操作的代码与此类似。 主要区别在于传递给 GetSpellingError 方法的参数。 对于 TextBox，传递插入符号位置的整数索引：
spellingError = myTextBox.GetSpellingError(caretIndex);
对于 RichTextBox，传递指定插入符号位置的 TextPointer：
spellingError = myRichTextBox.GetSpellingError(myRichTextBox.CaretPosition);
