您的位置：首页 > 理论基础 > 计算机网络

从 HTTP 上下载文件示例

2006-12-29 13:16 381 查看

从 HTTP 上下载文件示例，源码免费（有进度显示）

*直接运行下面代码就可以了，在.vfp8.0环境下测试成功！

* How to download data of this reference (DBF files) using HTTP
* 从 HTTP 上下载文件
*------------------------------------------------------------------
Clea
#Define INTERNET_OPEN_TYPE_DIRECT 1
#Define INTERNET_FLAG_NEED_FILE 16

#Define HTTP_QUERY_CONTENT_TYPE 1
#Define HTTP_QUERY_CONTENT_LENGTH 5

Do Decl && declare external functions
*If InternetCheckConnection("http://www.163.com/", 1, 0) <> 0 &&已经连接Internet
*Endif
* initialize Wininet library

Private hOpen
hOpen = InternetOpen ("vfp", INTERNET_OPEN_TYPE_DIRECT, 0, 0, 0)
If hOpen = 0
? "GetLastError:", GetLastError()
? "在本机上 WinInet 函数库无效"
Return
Endif

Local lcBaseUrl, lcDstPath, hFile, lcFile
lcBaseUrl = "http://ftpgz13.pconline.com.cn/pub/download/200203/Mp3RenameEasy.zip"&&根据实际修改这里的字符串
lcFile = "Mp3RenameEasy.zip"&&保存的文件名
lcDstPath = "C:\" &&保存的路径

* get a handle of the remote file
hFile = InternetOpenUrl (hOpen,;
lcBaseUrl , "", 0,;
INTERNET_FLAG_NEED_FILE, 0)

If hFile <> 0
?hfile
* even if there is no such file, the most evidently
* you will get an ASCII file in response (404 error page)
= http2local (hFile, lcDstPath + lcFile)
= InternetCloseHandle (hFile)
Else
? "网址不能打开"
? "错误号:", GetLastError()
Endif

* release WinInet library
= InternetCloseHandle (hOpen)
Return && main

*--------------------------------------------
Function http2local (hSource, lcTarget)
* reads data from a remote file
#Define TransferBuffer 4096
? lcTarget + " "

* create the target file

hTarget = Fcreate (lcTarget)
If (hTarget = -1)
?? "指定的目标文件无效"
Return -1
Endif

Local Buffer , BufLen , dwIndex
Buffer = Space(128)
BufLen = Len(Buffer)
dwIndex = 0
If HttpQueryInfo(hSource, HTTP_QUERY_CONTENT_LENGTH, @Buffer, @BufLen, @dwIndex) = 0
?"获取文件信息失败！"
Return -1
Endif
?
?"文件大小: " + Left(Buffer,buflen)+" / "

lnTotalBytesRead = 0
lnSec = Seconds()

Do While .T.
If Inkey() = 27 && 按 "Esc" 键
Exit
Endif
lcBuffer = Replicate(Chr(0), TransferBuffer)
lnBytesRead = 0

If InternetReadFile (hSource, @lcBuffer,TransferBuffer, @lnBytesRead) = 1

= Fwrite (hTarget, lcBuffer, lnBytesRead)
If lnBytesRead = 0
Exit
Endif
lnTotalBytesRead = lnTotalBytesRead + lnBytesRead
Wait Window Transform(Val(Buffer)/1024) + " KB / " + Transform(lnTotalBytesRead/1024) + " KB " Nowait

Else
Exit
Endif
DoEvents
Enddo

= Fclose (hTarget)
?? " " + Transform(lnTotalBytesRead) + " Bytes 完成用时: " + Transform(Seconds() - lnSec) + " 秒"
Return lnBytesRead
Endfunc

Procedure Decl
Declare Integer InternetCheckConnection In wininet.Dll ;
String lpszUrl ,;
Integer dwFlags ,;
Integer dwReserved

Declare Integer GetLastError In kernel32

Declare Integer InternetOpen In wininet;
STRING sAgent,;
INTEGER lAccessTypem,;
STRING sProxyName,;
STRING sProxyBypass,;
STRING lFlags

Declare Integer InternetCloseHandle In wininet Integer hInet

Declare Integer InternetOpenUrl In wininet;
INTEGER hInternet,;
STRING lpszUrl,;
STRING lpszHeaders,;
INTEGER dwHeadersLength,;
INTEGER dwFlags,;
INTEGER dwContext

Declare Integer InternetReadFile In wininet;
INTEGER hFile,;
STRING @ lpBuffer,;
INTEGER dwNumberOfBytesToRead,;
INTEGER @ lpdwNumberOfBytesRead

Declare Integer HttpQueryInfo In wininet ;
INTEGER hHttpRequest, ;
INTEGER lInfoLe

内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理

标签：

相关文章推荐

新的分享

章节导航