IdTCPServer1Execute事件在什么情况下被触发

2012-10-30 09:40:32 349 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

C++Builder 5项目实战：从经典VCL开发到现代化重构指南可视化组件库（VCL）作为高效的桌面应用开发框架，通过基于属性的组件化模型，实现了界面快速构建与业务逻辑的分离。其核心原理在于将UI元素封装为独立对象，通过事件驱动机制响应用户交互，在提升开发效率的同时，保持了底层C++代码的可控性。这一技术价值体现在能够大幅缩短从原型到产品的开发周期，特别适合需要快速迭代的工业控制、数据采集等场景。本文以经典著作《C++Builder 5编程实战》中的项目为例，深入探讨如何将基于BDE、Indy等传统组件的遗留系统，迁移至FireDAC、GDI+等现代技术栈，并解决多线程阅读详情

我用的indy 10.1.6，请问IdTCPServer1Execute事件在什么条件下才被触发？

1、在一次connect之后触发一次IdTCPServer1Execute事件。
2、服务器端收到一个TCP数据包就触发一次IdTCPServer1Execute事件。
3、服务器端收到一个带有数据部分的数据包就触发一次IdTCPServer1Execute事件。

还有在其他的情况下被触发？

...全文

LD14激光雷达与STM32F103C8T6（标准库）获取雷达360度数据（1） LD14激光雷达与STM32F103C8T6（标准库）获取雷达360度数据（1）阅读详情

didijiji

网络及通讯开发 1,317 成员 8,874 内容

+ 关注 + 加入社区

切换为时间正序

No_145015 2012-10-31

打赏
举报

只要有客户发送数据，就会激活 Server 的 OnExecute 事件

http://blog.csdn.net/gencheng/article/details/7275230

xjq2003 2012-10-30

打赏
举报

Summary
Event handler used to execute the task for a client connection.
Description
OnExecute is a TIdServerThreadEvents event handler used to execute the task for a client connection to the server. OnExecute is signalled when the Scheduler executes the thread or fiber associated with the client connection.
OnExecute receives a TIdContext argument that represents the task for the client connection, and contains a TIdTCPConnection instance for the client connection, and the thread or fiber that controls execution of the task. A protected procedure in the server that triggers OnExecute is assigned to the TIdContext, and eventually the thread or fiber acquired from the Scheduler for the server.

Use OnExecute to control the interaction between the client and the server during the lifetime of the client connection. This includes reading and/or writing commands and/or data supported in exchanges between the client and server. TIdTCPServer does not implement support for any given protocol used for communication exchanges between clients and the server.

When the thread or fiber is running, the OnExecute event handler is triggered inside a loop that continues to execute the event handler until the client is disconnected. This allows the OnExecute event handler procedure to be written in a straight-forward manner, and still yield to the Scheduler for the server.

The event handler can be used to interact with the client connection by read a command and/or writing a response dependent on the protocol in use for the session. When the command and/or response is handled, the event handler should be exited to allow the Scheduler to respond other client connections to the server. Using loops or polling inside the OnExecute event handler should be avoided to reduce the chance of interferring with the Scheduler for the server.

The preferred way to interrupt execution of the looped OnExecute event handler is to call the TIdContext.Connection.Disconnect method for the context instance.

For example:

TMyForm.MyServerExecute(AContext: TIdContext);
var
lCmd: string;
begin
lCmd := Trim(AContext.Connection.IOHandler.ReadLn);
if AnsiSameText(lCmd, 'HELP') then
begin
AContext.Connection.IOHandler.WriteLn('HELP');
AContext.Connection.IOHandler.WriteLn('QUIT');
AContext.Connection.IOHandler.WriteLn('GETTIMESTAMP');
AContext.Connection.IOHandler.WriteLn('');
end

else if AnsiSameText(lCmd, 'QUIT') then
begin
AContext.Connection.IOHandler.WriteLn('Goodbye...');
AContext.Connection.IOHandler.WriteLn('');
AContext.Connection.Disconnect;
end

else if AnsiSameText(lCmd, 'GETTIMESTAMP') then
begin
AContext.Connection.IOHandler.WriteLn(
FormatDateTime(Now, 'yyyy-mm-ddThh:nn:ss.zzz'));
AContext.Connection.IOHandler.WriteLn('');
end;
end;

Exceptions raised in the OnExecute event handler are caught in the executing thread or fiber. If the exception cannot be handled by the thread or fiber, it is re-raised and causes termination of the thread or fiber.

Use OnConnect to perform actions for the client after it is connected and prior to execution in the OnExecute event handler.

Use OnDisconnect to perform actions for the client after is has been disconnected, and exited from the OnExecute event handler.

Assign a TIdServerThreadEvent event handler procedure to OnExecute to respond to the event notification.

See Also
TIdServerThreadEvents
Class
TIdTCPServer

IdTCPServer1Execute事件在什么情况下被触发

相关推荐