(VB.NET UWP/WinRT) Paging User Photos with Cursor

Demonstrates how to iterate over the pages of user photos using a cursor.

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

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

' This example assumes a previously obtained an access token
Dim oauth2 As New Chilkat.OAuth2
oauth2.AccessToken = "FACEBOOK-ACCESS-TOKEN"

Dim rest As New Chilkat.Rest

' Connect to Facebook.
Dim success As Boolean = Await rest.ConnectAsync("graph.facebook.com",443,True,True)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


' Provide the authentication credentials (i.e. the access key)
rest.SetAuthOAuth2(oauth2)

' Indicate that we only want the photos the user has personally uploaded.
rest.AddQueryParam("type","uploaded")

' We could limit the number of photos per page using the "limit" field.
rest.AddQueryParam("limit","20")

' Get the 1st page of photos. (Not the actual image data, but the information about each photo.)
' See https://developers.facebook.com/docs/graph-api/reference/user/photos/ for more information.
Dim responseJson As String = Await rest.FullRequestNoBodyAsync("GET","/v2.7/me/photos")
If (rest.LastMethodSuccess <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


Dim json As New Chilkat.JsonObject
json.EmitCompact = False
json.Load(responseJson)
Debug.WriteLine(json.Emit())

' 
' See Parsing the Facebook User Photos for code showing how to parse the JSON photos content.
' 

' Get the "after" cursor.
Dim afterCursor As String = json.StringOf("paging.cursors.after")
While json.LastMethodSuccess = True

    Debug.WriteLine("after cursor: " & afterCursor)

    ' Prepare for getting the next page of photos.
    ' We can continue using the same REST object.
    ' If already connected, we'll continue using the existing connection.
    ' Otherwise, a new connection will automatically be made if needed.
    rest.ClearAllQueryParams()
    rest.AddQueryParam("type","uploaded")
    rest.AddQueryParam("limit","20")
    rest.AddQueryParam("after",afterCursor)

    responseJson = Await rest.FullRequestNoBodyAsync("GET","/v2.7/me/photos")
    If (rest.LastMethodSuccess <> True) Then
        Debug.WriteLine(rest.LastErrorText)
        Exit Sub
    End If


    json.Load(responseJson)
    ' See Parsing the Facebook User Photos for code showing how to parse the JSON photos content.

    Debug.WriteLine(json.Emit())

    ' Get the cursor for the next page.
    afterCursor = json.StringOf("paging.cursors.after")
End While

Debug.WriteLine("No more pages of photos.")