通过

演练:显示的语句完成

通过定义要提供完成的标识符，然后触发完成会话实现的语言为基础的功能 (如语句结束。 可以定义语句完成语言服务中，也可以定义拥有文件扩展名与内容类型，并显示该类型的完成，也可以触发现有内容类型的完成 (如 “纯文本”)。 本演练演示如何触发 “纯文本”内容类型的语句完成，是文本文件的内容类型。 “文本”内容类型为其他内容类型的上级，包括代码和 XML 文件。

，例如，语句完成通过键入某些字符通常触发通过键入一个标识符的开头 (如 “使用”。 它通过按空格键通常关闭，选项，或者输入进行选择。 通过键入字符触发的 IntelliSense 功能可以实现使用击键 ( IOleCommandTarget 界面) 和实现 IVsTextViewCreationListener 接口的处理程序提供程序的命令处理程序。 若要创建完成源，是标识符列表参与完成，请实现 ICompletionSource 接口和完成源提供程序 ( ICompletionSourceProvider 接口)。 提供程序是托管扩展性框架 (MEF)组成部分，并对导出源和控制器类和导入服务和代理，例如， ITextStructureNavigatorSelectorService，在文本缓冲区可以导航和 ICompletionBroker，负责触发完成会话。

本演练演示如何实现硬编码的语句完成设置标识符。 在完整的实现，语言服务和语言文档负责提供该目录。

系统必备

若要完成本演练，您必须安装 Visual Studio 2010 SDK。

备注

有关 Visual Studio SDK 的更多信息，请参见 扩展 Visual Studio 概述。若要查找有关中所列如何下载 Visual Studio SDK，请 Visual Studio Extensibility Developer Center 参见 MSDN 网站上。

创建 MEF 项目

创建 MEF 项目

  1. 创建一个编辑分类器项目。 将解决方案命名为 CompletionTest。

  2. 打开在 VSIX 清单编辑器中的 source.extension.vsixmanifest 文件。

  3. 确保 内容 归为包含一个 MEF 组件 内容类型，而 路径 设置为 CompletionTest.dll。

  4. 保存并关闭的 source.extension.vsixmanifest。

  5. 将下列引用添加到项目，并确保 CopyLocal 设置为 false:

    Microsoft.VisualStudio.Editor

    Microsoft.VisualStudio.Language.Intellisense

    Microsoft.VisualStudio.OLE.Interop

    Microsoft.VisualStudio.Shell.10.0

    Microsoft.VisualStudio.Shell.Immutable.10.0

    Microsoft.VisualStudio.TextManager.Interop

  6. 删除现有类文件。

实现完成源

完成源为集合设置标识符和添加内容负责以完成窗口中，当用户键入完成触发器，例如标识符的首字母。 在本示例中，标识符及其说明的是硬编码。AugmentCompletionSession 方法。 在最具体的使用，则应使用语言的分析器获取标记填充完成列表。

实现完成源

  1. 将类文件并将其命名为 TestCompletionSource。

  2. 添加下面的导入。

    Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.ComponentModel.Composition
Imports Microsoft.VisualStudio.Language.Intellisense
Imports Microsoft.VisualStudio.Text
Imports Microsoft.VisualStudio.Text.Operations
Imports Microsoft.VisualStudio.Utilities

    using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel.Composition;
using Microsoft.VisualStudio.Language.Intellisense;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Operations;
using Microsoft.VisualStudio.Utilities;

  3. 修改 TestCompletionSource 的类声明，以便它实现 ICompletionSource。

    Friend Class TestCompletionSource
    Implements ICompletionSource

    internal class TestCompletionSource : ICompletionSource

  4. 将源提供程序、文本缓冲区和列表的私有字段对应于标识符将参与完成会话) 的 Completion 对象 (。

    Private m_sourceProvider As TestCompletionSourceProvider
Private m_textBuffer As ITextBuffer
Private m_compList As List(Of Completion)

    private TestCompletionSourceProvider m_sourceProvider;
private ITextBuffer m_textBuffer;
private List<Completion> m_compList;

  5. 添加用于设置提供程序和源缓冲区的构造函数。 TestCompletionSourceProvider 类在后续步骤中定义。

    Public Sub New(ByVal sourceProvider As TestCompletionSourceProvider, ByVal textBuffer As ITextBuffer)
    m_sourceProvider = sourceProvider
    m_textBuffer = textBuffer
End Sub

    public TestCompletionSource(TestCompletionSourceProvider sourceProvider, ITextBuffer textBuffer)
{
    m_sourceProvider = sourceProvider;
    m_textBuffer = textBuffer;
}

  6. 通过添加包含完成要在上下文提供设置的完成执行 AugmentCompletionSession 方法。 设置的每完成包含设置 Completion 完成，并且对应于完成窗口的选项卡。 (在 Visual Basic 项目中，完成窗口 " 选项卡名为 常见 和 任何。)FindTokenSpanAtPosition 方法在下一步中定义。

    Private Sub AugmentCompletionSession(ByVal session As ICompletionSession, ByVal completionSets As IList(Of CompletionSet)) Implements ICompletionSource.AugmentCompletionSession
    Dim strList As New List(Of String)()
    strList.Add("addition")
    strList.Add("adaptation")
    strList.Add("subtraction")
    strList.Add("summation")

    m_compList = New List(Of Completion)()
    For Each str As String In strList
        m_compList.Add(New Completion(str, str, str, Nothing, Nothing))
    Next str

    completionSets.Add(New CompletionSet(
        "Tokens",
        "Tokens",
        FindTokenSpanAtPosition(session.GetTriggerPoint(m_textBuffer),
            session),
        m_compList,
        Nothing))
End Sub

    void ICompletionSource.AugmentCompletionSession(ICompletionSession session, IList<CompletionSet> completionSets)
{
    List<string> strList = new List<string>();
    strList.Add("addition");
    strList.Add("adaptation");
    strList.Add("subtraction");
    strList.Add("summation");
    m_compList = new List<Completion>();
    foreach (string str in strList)
        m_compList.Add(new Completion(str, str, str, null, null));

    completionSets.Add(new CompletionSet(
        "Tokens",    //the non-localized title of the tab 
        "Tokens",    //the display title of the tab
        FindTokenSpanAtPosition(session.GetTriggerPoint(m_textBuffer),
            session),
        m_compList,
        null));
}

  7. 以下方法用于查找从脱字号位置的当前单词。

    Private Function FindTokenSpanAtPosition(ByVal point As ITrackingPoint, ByVal session As ICompletionSession) As ITrackingSpan
    Dim currentPoint As SnapshotPoint = (session.TextView.Caret.Position.BufferPosition) - 1
    Dim navigator As ITextStructureNavigator = m_sourceProvider.NavigatorService.GetTextStructureNavigator(m_textBuffer)
    Dim extent As TextExtent = navigator.GetExtentOfWord(currentPoint)
    Return currentPoint.Snapshot.CreateTrackingSpan(extent.Span, SpanTrackingMode.EdgeInclusive)
End Function

    private ITrackingSpan FindTokenSpanAtPosition(ITrackingPoint point, ICompletionSession session)
{
    SnapshotPoint currentPoint = (session.TextView.Caret.Position.BufferPosition) - 1;
    ITextStructureNavigator navigator = m_sourceProvider.NavigatorService.GetTextStructureNavigator(m_textBuffer);
    TextExtent extent = navigator.GetExtentOfWord(currentPoint);
    return currentPoint.Snapshot.CreateTrackingSpan(extent.Span, SpanTrackingMode.EdgeInclusive);
}

  8. 执行 Dispose() 方法:

    Private m_isDisposed As Boolean 
Public Sub Dispose() Implements IDisposable.Dispose
    If Not m_isDisposed Then
        GC.SuppressFinalize(Me)
        m_isDisposed = True 
    End If 
End Sub

    private bool m_isDisposed;
public void Dispose()
{
    if (!m_isDisposed)
    {
        GC.SuppressFinalize(this);
        m_isDisposed = true;
    }
}

实现完成源提供程序

完成数据源提供程序是实例化完成源的 MEF 组件。

实现完成源提供程序

  1. 添加类被命名为该 TestCompletionSourceProvider 实现 ICompletionSourceProvider。 导出与 “纯文本” ContentTypeAttribute 的此类，并 NameAttribute “测试完成”。

    <Export(GetType(ICompletionSourceProvider)), ContentType("plaintext"), Name("token completion")>
Friend Class TestCompletionSourceProvider
    Implements ICompletionSourceProvider

    [Export(typeof(ICompletionSourceProvider))]
[ContentType("plaintext")]
[Name("token completion")]
internal class TestCompletionSourceProvider : ICompletionSourceProvider

  2. 导入 ITextStructureNavigatorSelectorService，将使用查找在完成源的当前单词。

    <Import()>
Friend Property NavigatorService() As ITextStructureNavigatorSelectorService

    [Import]
internal ITextStructureNavigatorSelectorService NavigatorService { get; set; }

  3. 执行 TryCreateCompletionSource 方法实例化完成源。

    Public Function TryCreateCompletionSource(ByVal textBuffer As ITextBuffer) As ICompletionSource Implements ICompletionSourceProvider.TryCreateCompletionSource
    Return New TestCompletionSource(Me, textBuffer)
End Function

    public ICompletionSource TryCreateCompletionSource(ITextBuffer textBuffer)
{
    return new TestCompletionSource(this, textBuffer);
}

实现完成订单处理程序提供程序

完成订单处理程序提供程序从 IVsTextViewCreationListener派生，侦听一个文本视图创建事件并将 IVsTextView (视图允许命令添加到 Visual Studio shell 命令字符串) 转换为 ITextView。 因为此类是 MEF 导出，还可以使用它来导入由命令处理程序可能需要的服务。

实现完成订单处理程序提供程序

  1. 将名为 TestCompletionCommandHandler 的文件。

  2. 使用语句，添加以下内容。

    Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.ComponentModel.Composition
Imports System.Runtime.InteropServices
Imports Microsoft.VisualStudio
Imports Microsoft.VisualStudio.Editor
Imports Microsoft.VisualStudio.Language.Intellisense
Imports Microsoft.VisualStudio.OLE.Interop
Imports Microsoft.VisualStudio.Shell
Imports Microsoft.VisualStudio.Text
Imports Microsoft.VisualStudio.Text.Editor
Imports Microsoft.VisualStudio.TextManager.Interop
Imports Microsoft.VisualStudio.Utilities

    using System;
using System.ComponentModel.Composition;
using System.Runtime.InteropServices;
using Microsoft.VisualStudio;
using Microsoft.VisualStudio.Editor;
using Microsoft.VisualStudio.Language.Intellisense;
using Microsoft.VisualStudio.OLE.Interop;
using Microsoft.VisualStudio.Shell;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Editor;
using Microsoft.VisualStudio.TextManager.Interop;
using Microsoft.VisualStudio.Utilities;

  3. 添加类被命名为该 TestCompletionHandlerProvider 实现 IVsTextViewCreationListener。 导出与 “标记完成处理程序” NameAttribute ， “纯文本” ContentTypeAttribute 和 EditableTextViewRoleAttribute 的此类。

    <Export(GetType(IVsTextViewCreationListener))>
<Name("token completion handler")>
<ContentType("plaintext")> <TextViewRole(PredefinedTextViewRoles.Editable)>
Friend Class TestCompletionHandlerProvider
    Implements IVsTextViewCreationListener

    [Export(typeof(IVsTextViewCreationListener))]
[Name("token completion handler")]
[ContentType("plaintext")]
[TextViewRole(PredefinedTextViewRoles.Editable)]
internal class TestCompletionHandlerProvider : IVsTextViewCreationListener

  4. 导入 IVsEditorAdaptersFactoryService，可以从 IVsTextView 转换为 ITextView、 ICompletionBroker和 SVsServiceProvider，可以访问标准 Visual Studio 服务。

    <Import()>
Friend AdapterService As IVsEditorAdaptersFactoryService = Nothing
<Import()>
Friend Property CompletionBroker() As ICompletionBroker
<Import()>
Friend Property ServiceProvider() As SVsServiceProvider

    [Import]
internal IVsEditorAdaptersFactoryService AdapterService = null;
[Import]
internal ICompletionBroker CompletionBroker { get; set; }
[Import]
internal SVsServiceProvider ServiceProvider { get; set; }

  5. 执行 VsTextViewCreated 方法实例化命令处理程序。

    Public Sub VsTextViewCreated(ByVal textViewAdapter As IVsTextView) Implements IVsTextViewCreationListener.VsTextViewCreated
    Dim textView As ITextView = AdapterService.GetWpfTextView(textViewAdapter)
    If textView Is Nothing Then 
        Return 
    End If 

    Dim createCommandHandler As Func(Of TestCompletionCommandHandler) = Function() New TestCompletionCommandHandler(textViewAdapter, textView, Me)
    textView.Properties.GetOrCreateSingletonProperty(createCommandHandler)
End Sub

    public void VsTextViewCreated(IVsTextView textViewAdapter)
{
    ITextView textView = AdapterService.GetWpfTextView(textViewAdapter);
    if (textView == null)
        return;

    Func<TestCompletionCommandHandler> createCommandHandler = delegate() { return new TestCompletionCommandHandler(textViewAdapter, textView, this); };
    textView.Properties.GetOrCreateSingletonProperty(createCommandHandler);
}

实现完成订单处理程序

因为语句完成由键击触发，则必须实现 IOleCommandTarget 接口以便接收和处理触发，提交，且关闭完成会话的键击。

实现完成订单处理程序

  1. 添加类被命名为该 TestCompletionCommandHandler 实现 IOleCommandTarget。

    Friend Class TestCompletionCommandHandler
    Implements IOleCommandTarget

    internal class TestCompletionCommandHandler : IOleCommandTarget

  2. 向命令处理程序 (向其中通过命令)，文本视图、允许您访问各种服务) 的命令处理程序提供程序 (和完成会话的私有字段。

    Private m_nextCommandHandler As IOleCommandTarget
Private m_textView As ITextView
Private m_provider As TestCompletionHandlerProvider
Private m_session As ICompletionSession

    private IOleCommandTarget m_nextCommandHandler;
private ITextView m_textView;
private TestCompletionHandlerProvider m_provider;
private ICompletionSession m_session;

  3. 添加用于设置文本视图和提供程序域的构造函数，并添加命令到命令字符串。

    Friend Sub New(ByVal textViewAdapter As IVsTextView, ByVal textView As ITextView, ByVal provider As TestCompletionHandlerProvider)
    Me.m_textView = textView
    Me.m_provider = provider

    'add the command to the command chain
    textViewAdapter.AddCommandFilter(Me, m_nextCommandHandler)
End Sub

    internal TestCompletionCommandHandler(IVsTextView textViewAdapter, ITextView textView, TestCompletionHandlerProvider provider)
{
    this.m_textView = textView;
    this.m_provider = provider;

    //add the command to the command chain
    textViewAdapter.AddCommandFilter(this, out m_nextCommandHandler);
}

  4. 通过将命令执行 QueryStatus 方法。

    Public Function QueryStatus(ByRef pguidCmdGroup As Guid, ByVal cCmds As UInteger, ByVal prgCmds() As OLECMD, ByVal pCmdText As IntPtr) As Integer Implements IOleCommandTarget.QueryStatus
    Return m_nextCommandHandler.QueryStatus(pguidCmdGroup, cCmds, prgCmds, pCmdText)
End Function

    public int QueryStatus(ref Guid pguidCmdGroup, uint cCmds, OLECMD[] prgCmds, IntPtr pCmdText)
{
    return m_nextCommandHandler.QueryStatus(ref pguidCmdGroup, cCmds, prgCmds, pCmdText);
}

  5. 实现 Exec 方法。 当此方法接收键击时，它必须执行这些操作之一:

    • 允许字符对缓冲区进行编写，然后触发或筛选完成 (印字字符执行)。

    • 提交完成，但是，不允许字符的缓冲区写入 (空白、选项卡和以下为此，在完成会话显示时)。

    • 允许命令传递到下处理程序 (其他命令)。

    因为此方法会显示用户界面，应确保，它不在自动化上下文调用通过调用 IsInAutomationFunction。

    Public Function Exec(ByRef pguidCmdGroup As Guid, ByVal nCmdID As UInteger, ByVal nCmdexecopt As UInteger, ByVal pvaIn As IntPtr, ByVal pvaOut As IntPtr) As Integer Implements IOleCommandTarget.Exec
    If VsShellUtilities.IsInAutomationFunction(m_provider.ServiceProvider) Then 
        Return m_nextCommandHandler.Exec(pguidCmdGroup, nCmdID, nCmdexecopt, pvaIn, pvaOut)
    End If 
    'make a copy of this so we can look at it after forwarding some commands 
    Dim commandID As UInteger = nCmdID
    Dim typedChar As Char = Char.MinValue
    'make sure the input is a char before getting it 
    If pguidCmdGroup = VSConstants.VSStd2K AndAlso nCmdID = CUInt(VSConstants.VSStd2KCmdID.TYPECHAR) Then
        typedChar = CChar(ChrW(CUShort(Marshal.GetObjectForNativeVariant(pvaIn))))
    End If 

    'check for a commit character 
    If nCmdID = CUInt(VSConstants.VSStd2KCmdID.RETURN) OrElse nCmdID = CUInt(VSConstants.VSStd2KCmdID.TAB) OrElse (Char.IsWhiteSpace(typedChar) OrElse Char.IsPunctuation(typedChar)) Then 
        'check for a a selection 
        If m_session IsNot Nothing AndAlso (Not m_session.IsDismissed) Then 
            'if the selection is fully selected, commit the current session 
            If m_session.SelectedCompletionSet.SelectionStatus.IsSelected Then
                m_session.Commit()
                'also, don't add the character to the buffer 
                Return VSConstants.S_OK
            Else 
                'if there is no selection, dismiss the session
                m_session.Dismiss()
            End If 
        End If 
    End If 

    'pass along the command so the char is added to the buffer 
    Dim retVal As Integer = m_nextCommandHandler.Exec(pguidCmdGroup, nCmdID, nCmdexecopt, pvaIn, pvaOut)
    Dim handled As Boolean = False 
    If (Not typedChar.Equals(Char.MinValue)) AndAlso Char.IsLetterOrDigit(typedChar) Then 
        If m_session Is Nothing OrElse m_session.IsDismissed Then ' If there is no active session, bring up completion
            Me.TriggerCompletion()
            m_session.Filter()
        Else 'the completion session is already active, so just filter
            m_session.Filter()
        End If
        handled = True 
    ElseIf commandID = CUInt(VSConstants.VSStd2KCmdID.BACKSPACE) OrElse commandID = CUInt(VSConstants.VSStd2KCmdID.DELETE) Then 'redo the filter if there is a deletion
        If m_session IsNot Nothing AndAlso (Not m_session.IsDismissed) Then
            m_session.Filter()
        End If
        handled = True 
    End If 
    If handled Then 
        Return VSConstants.S_OK
    End If 
    Return retVal
End Function

    public int Exec(ref Guid pguidCmdGroup, uint nCmdID, uint nCmdexecopt, IntPtr pvaIn, IntPtr pvaOut)
{
    if (VsShellUtilities.IsInAutomationFunction(m_provider.ServiceProvider))
    {
        return m_nextCommandHandler.Exec(ref pguidCmdGroup, nCmdID, nCmdexecopt, pvaIn, pvaOut);
    }
    //make a copy of this so we can look at it after forwarding some commands 
    uint commandID = nCmdID;
    char typedChar = char.MinValue;
    //make sure the input is a char before getting it 
    if (pguidCmdGroup == VSConstants.VSStd2K && nCmdID == (uint)VSConstants.VSStd2KCmdID.TYPECHAR)
    {
        typedChar = (char)(ushort)Marshal.GetObjectForNativeVariant(pvaIn);
    }

    //check for a commit character 
    if (nCmdID == (uint)VSConstants.VSStd2KCmdID.RETURN
        || nCmdID == (uint)VSConstants.VSStd2KCmdID.TAB
        || (char.IsWhiteSpace(typedChar) || char.IsPunctuation(typedChar)))
    {
        //check for a a selection 
        if (m_session != null && !m_session.IsDismissed)
        {
            //if the selection is fully selected, commit the current session 
            if (m_session.SelectedCompletionSet.SelectionStatus.IsSelected)
            {
                m_session.Commit();
                //also, don't add the character to the buffer 
                return VSConstants.S_OK;
            }
            else
            {
                //if there is no selection, dismiss the session
                m_session.Dismiss();
            }
        }
    }

    //pass along the command so the char is added to the buffer 
    int retVal = m_nextCommandHandler.Exec(ref pguidCmdGroup, nCmdID, nCmdexecopt, pvaIn, pvaOut);
    bool handled = false;
    if (!typedChar.Equals(char.MinValue) && char.IsLetterOrDigit(typedChar))
    {
        if (m_session == null || m_session.IsDismissed) // If there is no active session, bring up completion
        {
            this.TriggerCompletion();
            m_session.Filter();
        }
        else     //the completion session is already active, so just filter
        {
            m_session.Filter();
        }
        handled = true;
    }
    else if (commandID == (uint)VSConstants.VSStd2KCmdID.BACKSPACE   //redo the filter if there is a deletion
        || commandID == (uint)VSConstants.VSStd2KCmdID.DELETE)
    {
        if (m_session != null && !m_session.IsDismissed)
            m_session.Filter();
        handled = true;
    }
    if (handled) return VSConstants.S_OK;
    return retVal;
}

  6. 下面的代码是触发完成会话的私有方法。

    Private Function TriggerCompletion() As Boolean 
    'the caret must be in a non-projection ___location  
    Dim caretPoint As SnapshotPoint? = m_textView.Caret.Position.Point.GetPoint(Function(textBuffer) ((Not textBuffer.ContentType.IsOfType("projection"))), PositionAffinity.Predecessor)
    If Not caretPoint.HasValue Then 
        Return False 
    End If

    m_session = m_provider.CompletionBroker.CreateCompletionSession(m_textView, caretPoint.Value.Snapshot.CreateTrackingPoint(caretPoint.Value.Position, PointTrackingMode.Positive), True)

    'subscribe to the Dismissed event on the session  
    AddHandler m_session.Dismissed, AddressOf OnSessionDismissed
    m_session.Start()

    Return True 
End Function

    private bool TriggerCompletion()
{
    //the caret must be in a non-projection ___location 
    SnapshotPoint? caretPoint =
    m_textView.Caret.Position.Point.GetPoint(
    textBuffer => (!textBuffer.ContentType.IsOfType("projection")), PositionAffinity.Predecessor);
    if (!caretPoint.HasValue)
    {
        return false;
    }

    m_session = m_provider.CompletionBroker.CreateCompletionSession
 (m_textView,
        caretPoint.Value.Snapshot.CreateTrackingPoint(caretPoint.Value.Position, PointTrackingMode.Positive),
        true);

    //subscribe to the Dismissed event on the session 
    m_session.Dismissed += this.OnSessionDismissed;
    m_session.Start();

    return true;
}

  7. 下面的代码是从 Dismissed 取消订阅事件的私有方法。

    Private Sub OnSessionDismissed(ByVal sender As Object, ByVal e As EventArgs)
    RemoveHandler m_session.Dismissed, AddressOf OnSessionDismissed
    m_session = Nothing 
End Sub

    private void OnSessionDismissed(object sender, EventArgs e)
{
    m_session.Dismissed -= this.OnSessionDismissed;
    m_session = null;
}

生成并测试代码

若要测试此代码，请生成 CompletionTest 解决方案并运行在的实验实例。

生成和测试 CompletionTest 解决方案

  1. 生成解决方案。

  2. 当您运行在调试器中查看此项目， Visual Studio 的第二个实例进行实例化。

  3. 创建一个文本文件并键入包含单词 “添加”的某些文本。

  4. 因为您首先键入 “a”然后 “d”，包含 “添加”和 “条件”的列表应显示。 通知添加中选择。 当您键入另一个 “d”时，列表应包含 “仅添加”，现在处于选中状态。 可以通过按空格键进行 “添加”， tab 或 enter，或者通过键入的 ESC 或其他字符关闭列表。

请参见

任务

演练:链接到文件扩展名的内容类型