appwrite/docs/examples/0.7.x/server-dotnet/examples/database/update-collection.md

using Appwrite;

Client client = new Client();

client
  .SetEndPoint("https://[HOSTNAME_OR_IP]/v1") // Your API Endpoint
  .SetProject("5df5acd0d48c2") // Your project ID
  .SetKey("919c2d18fb5d4...a2ae413da83346ad2") // Your secret API key
;

Database database = new Database(client);

HttpResponseMessage result = await database.UpdateCollection("[COLLECTION_ID]", "[NAME]", [List<object>], [List<object>]);