enablecontentresponseonwrite-sample-delete-disable.cs

ItemResponse<ToDoActivity> readItemResponse = await this.container.ReadItemAsync(
  id: "<id>", 
  new PartitionKey("<partitionKeyValue>"));

ToDoActivity someItem = readItemResponse.Resource;
// Apply some modification
someItem.value = 5;

ItemResponse<ToDoActivity> itemResponse = await this.container.ReplaceItemAsync<ToDoActivity>(
  id: "<id>", 
  item: someItem,
  new PartitionKey("<partitionKeyValue>"),
  requestOptions : new ItemRequestOptions() { EnableContentResponseOnWrite = false });

ToDoActivity responseContent = itemResponse.Resource; // <-- This will be null now

double consumedRus = itemResponse.Headers.RequestCharge;
string etag = itemResponse.Headers.ETag;
string session = itemResponse.Headers.Session;