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VDF supports HTTP file transfers. Transferring a file using HTTP instead of FTP is useful when files need to be downloaded from a webserver that does not implement FTP for security reasons.
DAC provides the cHTTPTransfer class which also quick creation of a HTTPTransfer object using the Studio.
The minimum to download a file is:
1. Create the HTTPTranfer object form the toolbar.
2. Set the properties.
a. psRemoteHost - www.covesys.com
b. psAcceptTypes - blank (see below)
c. psSaveasFile - destination file name
3. Create a button with the OnClick message set to:
Procedure OnClick
Integer iRetval
Get HTTPGetRequest of oHttpTransfer {source file name} to iRetval
End_Procedure
Issues:
The HTTPTranfer object does a GET from the webserver. The object and the webserver try to figure out what type file is being transfer which can get messy. The psAcceptTypes property allows you to restrict the types of files the GET will return, but since you are asking for a particulare file you don't need this. Leaving it blank will allow you to download any type of file - as long as the webserver knows what type of file it is.
The most common types of files are handled: EXE, PDF, ZIP, OCX...
The below links describe what the Content-Type stuff is all about.
Contributed By:
Frank Valcarcel
Company: Cove Systems, Inc.
email: fv@covesys.com
Web Site: http://www.covesys.com
Web Links Related to this Article
HttpOpenRequest
URL=http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wcesdkr/html/_wcesdk_win32_HttpOpenRequest.asp
MIME Type Detection in Internet Explorer
URL=http://msdn.microsoft.com/library/default.asp?url=/workshop/networking/moniker/overview/appendix_a.asp
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