Today's plan

1. Use Indy to download Sina homepage text over HTTP -- OK
2. Use Indy to download common files through HTTP -- OK
3. Open a new thread and use Indy to implement HTTP to download Sina homepage text -- OK
4. Open a new thread and use Indy to implement HTTP to download Sina homepage text and ensure thread security-OK
5. Obtain the remote file size -- OK
Memo: You need to use get to retrieve Content-Length from the response. Reading HTTP ......
Memo: Response found in tidhttp, which contains the attribute contentlength
Result: connect to the server first, and then use the head method and response to complete the task.
6. Use a tcp client to achieve connection and disconnection -- OK
7. Use a tcp client to send and accept commands-failed
Memo: used to send commands in the HTTP protocol and learn from them at a lower level.
Result: www.sina.com.cn and www.cnblogs.com are used as experimental objects. It is very difficult to directly use HTTP to send and accept TCP/IP commands. I decided to suspend this test method. Instead, I studied the tidhttp function and returned to the HTTP level to see how to obtain the file information fed back by the GET command. The TCP/IP Command Transmission and acceptance switch to self-writing server for two-way debugging.
8. Track the download process-OK
Memo: the message sending and receiving are intercepted with idconnectionintercept, but the form is tstream ......
Result: register the onwork event directly.
9. Use what you learned during the day to create a simple download tool and use a progressbar to display the download progress-OK
Memo: pay extra attention to the excessive URL Parsing work and decide to suspend this out-of-band aspect.
Memo: Later I found a uriparse. It seems that Indy has taken care of everything ......
Result: http://files.cnblogs.com/taowen/SimpleHTTPDonwloader.rar