tencent cloud

    // 设置消息扩展
    var list = new List<MessageExtension>
    {
      new MessageExtension
      {
        message_extension_key = "key",
        message_extension_value = "value"
      }
    };
    TIMResult res = TencentIMSDK.MsgSetMessageExtensions(message, list, (int code, string desc, List<MessageExtensionResult> results, string user_data)=>{
      // 设置消息扩展异步结果
    });

    // 获取消息扩展
    TIMResult res = TencentIMSDK.MsgGetMessageExtensions(message, (int code, string desc, List<MessageExtension> list, string user_data)=>{
      // 获取消息扩展异步结果
    });

    // 删除消息扩展
    var list = new List<MessageExtension>
    {
      new MessageExtension
      {
        message_extension_key = "key",
        message_extension_value = "value"
      }
    };
    TIMResult res = TencentIMSDK.MsgDeleteMessageExtensions(message, list, (int code, string desc, List<MessageExtensionResult> results, string user_data)=>{
      // 删除消息扩展异步结果
    });

    // 添加高级消息的事件监听器
    TencentIMSDK.SetMsgExtensionsChangedCallback((string message_id, List<MessageExtension> message_extension_array, string user_data) => {
      // message_extension_array 为被修改之后的消息扩展对象列表
    });
    TencentIMSDK.SetMsgExtensionsDeletedCallback((string message_id, List<MessageExtension> message_extension_array, string user_data) => {
      // message_extension_array 为被删除之后的消息扩展对象列表
    });