データの変更を監視

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()            .Match(change => change.OperationType == ChangeStreamOperationType.Update);
// Opens a change streams and print the changes as they're receivedusing (var cursor = collection.Watch(pipeline)){    foreach (var change in cursor.ToEnumerable())    {        Console.WriteLine("Received the following change: " + change);    }}

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()            .Match(change => change.OperationType == ChangeStreamOperationType.Update);
// Opens a change stream and prints the changes as they're receivedusing (var cursor = await collection.WatchAsync(pipeline)){    await cursor.ForEachAsync(change =>    {        Console.WriteLine("Received the following change: " + change);    });}

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()    .ChangeStreamSplitLargeEvent();
using var cursor = collection.Watch(pipeline);foreach (var completeEvent in GetNextChangeStreamEvent(cursor.ToEnumerable().GetEnumerator())){    Console.WriteLine("Received the following change: " + completeEvent.BackingDocument);}

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()    .ChangeStreamSplitLargeEvent();
using var cursor = await collection.WatchAsync(pipeline);await foreach (var completeEvent in GetNextChangeStreamEventAsync(cursor)){    Console.WriteLine("Received the following change: " + completeEvent.BackingDocument);}

// Fetches the next complete change stream eventprivate static IEnumerable<ChangeStreamDocument<TDocument>> GetNextChangeStreamEvent<TDocument>(IEnumerator<ChangeStreamDocument<TDocument>> changeStreamEnumerator){    while (changeStreamEnumerator.MoveNext())    {        var changeStreamEvent = changeStreamEnumerator.Current;        if (changeStreamEvent.SplitEvent != null)        {            var fragment = changeStreamEvent;            while (fragment.SplitEvent.Fragment < fragment.SplitEvent.Of)            {                changeStreamEnumerator.MoveNext();                fragment = changeStreamEnumerator.Current;                MergeFragment(changeStreamEvent, fragment);            }        }        yield return changeStreamEvent;    }}
// Merges a fragment into the base eventprivate static void MergeFragment<TDocument>(    ChangeStreamDocument<TDocument> changeStreamEvent,    ChangeStreamDocument<TDocument> fragment){    foreach (var element in fragment.BackingDocument)    {        if (element.Name != "_id" && element.Name != "splitEvent")        {            changeStreamEvent.BackingDocument[element.Name] = element.Value;         }    }}

// Fetches the next complete change stream eventprivate static async IAsyncEnumerable<ChangeStreamDocument<TDocument>> GetNextChangeStreamEventAsync<TDocument>(    IAsyncCursor<ChangeStreamDocument<TDocument>> changeStreamCursor){    var changeStreamEnumerator = GetNextChangeStreamEventFragmentAsync(changeStreamCursor).GetAsyncEnumerator();    while (await changeStreamEnumerator.MoveNextAsync())    {        var changeStreamEvent = changeStreamEnumerator.Current;        if (changeStreamEvent.SplitEvent != null)        {            var fragment = changeStreamEvent;            while (fragment.SplitEvent.Fragment < fragment.SplitEvent.Of)            {                await changeStreamEnumerator.MoveNextAsync();                fragment = changeStreamEnumerator.Current;                MergeFragment(changeStreamEvent, fragment);            }        }        yield return changeStreamEvent;    }}
private static async IAsyncEnumerable<ChangeStreamDocument<TDocument>> GetNextChangeStreamEventFragmentAsync<TDocument>(    IAsyncCursor<ChangeStreamDocument<TDocument>> changeStreamCursor){    while (await changeStreamCursor.MoveNextAsync())    {        foreach (var changeStreamEvent in changeStreamCursor.Current)        {            yield return changeStreamEvent;        }    }}
// Merges a fragment into the base eventprivate static void MergeFragment<TDocument>(    ChangeStreamDocument<TDocument> changeStreamEvent,    ChangeStreamDocument<TDocument> fragment){    foreach (var element in fragment.BackingDocument)    {        if (element.Name != "_id" && element.Name != "splitEvent")        {            changeStreamEvent.BackingDocument[element.Name] = element.Value;        }    }}

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()    .Match(change => change.OperationType == ChangeStreamOperationType.Update);
var options = new ChangeStreamOptions{    FullDocument = ChangeStreamFullDocumentOption.UpdateLookup,};
using (var cursor = collection.Watch(pipeline, options)){    foreach (var change in cursor.ToEnumerable())    {        Console.WriteLine(change.FullDocument.ToBsonDocument());    }}

var pipeline = new EmptyPipelineDefinition<ChangeStreamDocument<Restaurant>>()    .Match(change => change.OperationType == ChangeStreamOperationType.Update);
var options = new ChangeStreamOptions{    FullDocument = ChangeStreamFullDocumentOption.UpdateLookup,};
using var cursor = await collection.WatchAsync(pipeline, options);await cursor.ForEachAsync(change =>{    Console.WriteLine(change.FullDocument.ToBsonDocument());});