(VB.NET UWP/WinRT) SharePoint -- Download File (Site Collection)

Demonstrates how to download a file from SharePoint located in the /Documents folder in a site within a site collection.

The format for a URL for a resource contained in a site within a site collection is like this:

https://contoso.com/sites/teamA/_api/web/GetFolderByServerRelativeUrl('/sites/teamA/Documents')/Files('SomeDocument.docx')/$value

Notice that the "/sites/teamA" (where "teamA" is the name of the site) occurs twice in the URL.

For more information, see https://docs.microsoft.com/en-us/sharepoint/sites/sites-and-site-collections-overview

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

' This requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' -------------------------------------------------------------------------
' The following comments apply to SharePoint Windows classic authentication.
' -------------------------------------------------------------------------
' For example, imagine our SharePoint endpoint is https://xyzoffice.mycompany.com/
' The SHAREPOINT_NTLM_DOMAIN would be "mycompany.com"
' The SHAREPOINT_HTTPS_DOMAIN would be "xyzoffice.mycompany.com"
' Also, the SHAREPOINT_USERNAME would be just the name, not a full email address.
' for example, "chilkat" instead of "chilkat@mycompany.com"

Dim http As New Chilkat.Http

' If SharePoint Windows classic authentication is used, then set the 
' Login, Password, LoginDomain, and NtlmAuth properties.
http.Login = "SHAREPOINT_USERNAME"
http.Password = "SHAREPOINT_PASSWORD"
http.LoginDomain = "SHAREPOINT_NTLM_DOMAIN"
http.NtlmAuth = True

' -------------------------------------------------------------------------
' The more common case is to use SharePoint Online authentication (via the SPOIDCRL cookie).
' If so, do not set Login, Password, LoginDomain, and NtlmAuth, and instead
' establish the cookie as shown at SharePoint Online Authentication
' -------------------------------------------------------------------------

' This example downloads the file named "Domain Name created for Exchange.docx"

' Note: I was initially confused by the "$value" part of the URL. 
' When I see something like $value, I immediately think that it's some sort of
' variable or placeholder to be replaced with an actual value.  In this case,
' the "$value" is literally part of the URL.  It's not replace with anything.

' --------------------------------------------------------------------------------
' IMPORTANT: The format for a URL within a site collection is like this:
' https://SHAREPOINT_HTTPS_DOMAIN/sites/teamA/_api/web/GetFolderByServerRelativeUrl('/sites/teamA/Documents')/Files('Domain Name created for Exchange.docx')/$value
' 
' Notice that "/sites/teamA" is specified twice in the above sample URL.
' --------------------------------------------------------------------------------


Dim url As String = "https://SHAREPOINT_HTTPS_DOMAIN/sites/teamA/_api/web/GetFolderByServerRelativeUrl('/sites/teamA/Documents')/Files('Domain Name created for Exchange.docx')/$value"
Dim localFilePath As String = "qa_output/x.docx"

Dim success As Boolean = Await http.DownloadAsync(url,localFilePath)
If (success <> True) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("File successfully downloaded from a SharePoint site within a site collection.")