扩展 Visual Studio 文档

文档是 Visual Studio 中打开的文件的内存中表示形式。 它由 名字对象引用，这是一个绝对 Uri 使用 file:// 方案。 文档由 DocumentSnapshot 具有以下属性的类表示：

• Moniker
• IsDirty
• IsReadOnly
• IsInitialized

该 DocumentsExtensibility 对象提供用于获取和使用 DocumentSnapshot 对象实例的各种方法。

使用文档

本指南旨在介绍使用文档时的首要用户方案：

• 打开文档
• 获取文本文档快照
• 响应与文档相关的事件

打开文档

给定磁盘上文件的路径后，在 Visual Studio 中打开该文件非常简单：

DocumentsExtensibility documents = this.Extensibility.Documents();

Uri uri = new Uri(@"C:\path\to\Class1.cs", UriKind.Absolute);
DocumentSnapshot document = await documents.OpenDocumentAsync(uri, cancellationToken);

// optionally do something with the document

获取文本文档快照

A DocumentSnapshot 是文档的抽象表示形式。 如果要在一个DocumentSnapshot中读取或写入文本，则可以使用ITextDocumentSnapshot接口（可以使用扩展方法获取AsTextDocumentAsync该接口）。DocumentSnapshot

public override async Task ExecuteCommandAsync(IClientContext context, CancellationToken cancellationToken)
{
    DocumentsExtensibility documents = this.Extensibility.Documents();

    Uri moniker = await context.GetSelectedPathAsync(cancellationToken);
    DocumentSnapshot document = await documents.GetDocumentAsync(moniker, cancellationToken);
    ITextDocumentSnapshot snapshot = await document.AsTextDocumentAsync(this.Extensibility, cancellationToken);

    // insert the current date/time
    EditorExtensibility editor = this.Extensibility.Editor();
    using ITextViewSnapshot textView = await context.GetActiveTextViewAsync(cancellationToken);

    await editor.EditAsync(
        batch => snapshot.AsEditable(batch).Replace(textView.Selection.Extent, DateTime.Now.ToString()),
        cancellationToken);
}

响应与文档相关的事件

在某些情况下，组件可能需要对与文档相关的事件做出反应（即打开、关闭或保存事件时）。 这可以通过实现 IDocumentEventsListener 接口以及用于 DocumentsExtensibility.SubscribeAsync 设置事件订阅来实现。

internal sealed class SubscribeCommand : Command, IToggleCommand
{
    private IDisposable? subscription;

    bool? IToggleCommand.IsChecked => this.subscription is not null;

    public override async Task ExecuteCommandAsync(IClientContext context, CancellationToken cancellationToken)
    {
        if (this.subscription is null)
        {
            // subscribe for events
            this.subscription = await Subscription.CreateInstanceAsync(this.Extensibility, cancellationToken);
        }
        else
        {
            // remove the event subscription
            this.subscription.Dispose();
            this.subscription = null;
        }

        this.OnPropertyChanged(new PropertyChangedEventArgs(nameof(IToggleCommand.IsChecked)));
    }

    private class Subscription : IDisposable, IDocumentEventsListener
    {
        private readonly OutputWindowExtensibility output;
        private IDisposable? rawSubscription;

        private Subscription(VisualStudioExtensibility extensibility)
        {
            this.output = extensibility.Views().Output;
        }

        public static async Task<Subscription> CreateInstanceAsync(
            VisualStudioExtensibility extensibility,
            CancellationToken cancellationToken)
        {
            var subscription = new Subscription(extensibility);

            DocumentsExtensibility documents = extensibility.Documents();
            subscription.rawSubscription = await documents.SubscribeAsync(subscription, filterRegex: null, cancellationToken);

            return subscription;
        }

        public void Dispose()
        {
            this.rawSubscription?.Dispose();
            this.rawSubscription = null;
        }

        Task IDocumentEventsListener.ClosedAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.ClosedAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.HiddenAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.HiddenAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.OpenedAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.OpenedAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.RenamedAsync(RenamedDocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.RenamedAsync ({e.OldMoniker} -> {e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.SavedAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.SavedAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.SavingAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.SavingAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        Task IDocumentEventsListener.ShownAsync(DocumentEventArgs e, CancellationToken token)
        {
            string text = $"IDocumentEventsListener.ShownAsync ({e.Moniker})";
            return this.OutputEventTextAsync(text, token);
        }

        private async Task OutputEventTextAsync(string text, CancellationToken token)
        {
            using OutputWindow outputWindow = await this.output.GetChannelAsync(
                identifier: "Document Sample Command Output",
                displayNameResourceId: nameof(Strings.DocumentsSampleOutputWindowPaneName),
                token);

            await outputWindow.Writer.WriteLineAsync($"Event received: {text}");
        }
    }
}

后续步骤

• 按照“入门”部分中的“创建项目”快速入门进行操作。