Chilkat Examples

ChilkatHOMEAndroid™Classic ASPCC++C#Mono C#.NET Core C#C# UWP/WinRTDataFlexDelphi ActiveXDelphi DLLVisual FoxProJavaLianjaMFCObjective-CPerlPHP ActiveXPHP ExtensionPowerBuilderPowerShellPureBasicCkPythonChilkat2-PythonRubySQL ServerSwift 2Swift 3,4,5...TclUnicode CUnicode C++Visual Basic 6.0VB.NETVB.NET UWP/WinRTVBScriptXojo PluginNode.jsExcelGo

Visual Basic 6.0 Web API Examples

Primary Categories

AWS Translate
Activix CRM
Amazon MWS
Azure Maps
Azure Monitor
Azure OAuth2
Azure Storage Accounts
Global Payments
Google Search Console
Hungary NAV Invoicing

Microsoft Calendar
Microsoft Group
Microsoft Tasks and Plans
Okta OAuth/OIDC
OneLogin OIDC
Walmart v3




(Visual Basic 6.0) Facebook Download all Photos to Local Files

Demonstrates how to download all of one's Facebook photos to a local filesystem directory. This sample code keeps a local cache to avoid re-downloading the same photos twice. The program can be run again after a time, and it will download only photos that haven't yet been downloaded.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

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

' This example will use a local disk cache to avoid re-fetching the same
' photo id after it's been fetched once.
Dim fbCache As New ChilkatCache
' The cache will use 1 level of 256 sub-directories.
fbCache.Level = 1
' Use a directory path that makes sense on your operating system..
fbCache.AddRoot "C:/fbCache"

' This example assumes a previously obtained an access token
Dim oauth2 As New ChilkatOAuth2
oauth2.AccessToken = "FACEBOOK-ACCESS-TOKEN"

Dim rest As New ChilkatRest

' Connect to Facebook.
Dim success As Long
success = rest.Connect("",443,1,1)
If (success <> 1) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

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

' There are two choices:  
' We can choose to download the photos the person is tagged in or has uploaded
' by setting type to "tagged" or "uploaded".
success = rest.AddQueryParam("type","uploaded")

' To download all photos, we begin with an outer loop that iterates over
' the list of photo nodes in pages.  Each page returned contains a list of 
' photo node ids.  Each photo node id must be retrieved to get the download URL(s)
' of the actual image.

' I don't know the max limit for the number of records that can be downloaded at once.
success = rest.AddQueryParam("limit","100")

' Get the 1st page of photos ids.
' See for more information.
Dim responseJson As String
responseJson = rest.FullRequestNoBody("GET","/v2.7/me/photos")
If (rest.LastMethodSuccess <> 1) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

Dim photoJson As New ChilkatJsonObject
Dim saPhotoUrls As New CkStringArray
Dim sbPhotoIdPath As New ChilkatStringBuilder

Dim json As New ChilkatJsonObject
json.EmitCompact = 0
success = json.Load(responseJson)

Dim i As Long
Dim photoId As String
Dim imageUrl As String

' Get the "after" cursor.
Dim afterCursor As String
afterCursor = json.StringOf("paging.cursors.after")
Do While json.LastMethodSuccess = 1

    Debug.Print "-------------------"
    Debug.Print "afterCursor = " & afterCursor

    ' For each photo id in this page...
    i = 0
    Dim numItems As Long
    numItems = json.SizeOfArray("data")
    Do While i < numItems
        json.I = i
        photoId = json.StringOf("data[i].id")
        Debug.Print "photoId = " & photoId

        ' We need to fetch the JSON for this photo.  Check to see if it's in the local disk cache,
        ' and if not, then get it from Facebook.
        Dim photoJsonStr As String
        photoJsonStr = fbCache.FetchText(photoId)
        If (fbCache.LastMethodSuccess = 0) Then
            ' It's not locally available, so get it from Facebook..
            success = sbPhotoIdPath.Append("/v2.7/")
            success = sbPhotoIdPath.Append(photoId)

            success = rest.ClearAllQueryParams()
            success = rest.AddQueryParam("fields","id,album,images")

            Debug.Print "Fetching photo node from Facebook..."

            ' This REST request will continue using the existing connection.
            ' If the connection was closed, it will automatically reconnect to send the request.
            photoJsonStr = rest.FullRequestNoBody("GET",sbPhotoIdPath.GetAsString())
            If (rest.LastMethodSuccess <> 1) Then
                Debug.Print rest.LastErrorText
                Exit Sub
            End If

            ' Add the photo JSON to the local cache.
            success = fbCache.SaveTextNoExpire(photoId,"",photoJsonStr)
        End If

        ' Parse the photo JSON and add the main photo download URL to saPhotoUrls
        ' There may be multiple URLs in the images array, but the 1st one is the largest and main photo URL.
        ' The others are smaller sizes of the same photo.
        success = photoJson.Load(photoJsonStr)
        imageUrl = photoJson.StringOf("images[0].source")
        If (photoJson.LastMethodSuccess = 1) Then

            ' Actually, we'll add a small JSON document that contains both the image ID and the URL.
            Dim imgUrlJson As New ChilkatJsonObject
            success = imgUrlJson.AppendString("id",photoId)
            success = imgUrlJson.AppendString("url",imageUrl)
            success = saPhotoUrls.Append(imgUrlJson.Emit())
            Debug.Print "imageUrl = " & imageUrl
        End If

        i = i + 1

    ' Prepare for getting the next page of photos ids.
    ' 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.
    success = rest.ClearAllQueryParams()
    success = rest.AddQueryParam("type","uploaded")
    success = rest.AddQueryParam("limit","20")
    success = rest.AddQueryParam("after",afterCursor)

    ' Get the next page of photo ids.
    responseJson = rest.FullRequestNoBody("GET","/v2.7/me/photos")
    If (rest.LastMethodSuccess <> 1) Then
        Debug.Print rest.LastErrorText
        Exit Sub
    End If

    success = json.Load(responseJson)
    afterCursor = json.StringOf("paging.cursors.after")

Debug.Print "No more pages of photos."

' Now iterate over the photo URLs and download each to a file.
' We can use Chilkat HTTP.  No Facebook authorization (access token) is required to download
' the photo once the URL is known.  
Dim http As New ChilkatHttp

' We'll cache the image data so that if run again, we don't re-download the same image again.
Dim numUrls As Long
numUrls = saPhotoUrls.Count
i = 0
Dim urlJson As New ChilkatJsonObject
Dim imageBytes() As Byte
Dim fac As New CkFileAccess

Do While i < numUrls
    success = urlJson.Load(saPhotoUrls.GetString(i))
    photoId = urlJson.StringOf("id")
    imageUrl = urlJson.StringOf("url")

    ' Check the local cache for the image data.
    ' Only download and save if not already cached.
    imageBytes = fbCache.FetchFromCache(imageUrl)
    If (fbCache.LastMethodSuccess = 0) Then
        '  This photo needs to be downloaded.

        Dim sbImageUrl As New ChilkatStringBuilder
        success = sbImageUrl.Append(imageUrl)

        ' Let's form a filename..
        Dim extension As String
        extension = ".jpg"
        If (sbImageUrl.Contains(".gif",0) = 1) Then
            extension = ".gif"
        End If

        If (sbImageUrl.Contains(".png",0) = 1) Then
            extension = ".png"
        End If

        If (sbImageUrl.Contains(".tiff",0) = 1) Then
            extension = ".tiff"
        End If

        If (sbImageUrl.Contains(".bmp",0) = 1) Then
            extension = ".bmp"
        End If

        Dim sbLocalFilePath As New ChilkatStringBuilder
        success = sbLocalFilePath.Append("C:/Photos/facebook/uploaded/")
        success = sbLocalFilePath.Append(photoId)
        success = sbLocalFilePath.Append(extension)

        imageBytes = http.QuickGet(imageUrl)
        If (http.LastMethodSuccess <> 1) Then
            Debug.Print http.LastErrorText
            Exit Sub
        End If

        ' We've downloaded the photo image bytes into memory.
        ' Save it to the cache AND save it to the output file.
        success = fbCache.SaveToCacheNoExpire(imageUrl,"",imageBytes)
        success = fac.WriteEntireFile(sbLocalFilePath.GetAsString(),imageBytes)

        Debug.Print "Downloaded to " & sbLocalFilePath.GetAsString()
    End If

    i = i + 1

Debug.Print "Finished downloading all Facebook photos!"


© 2000-2020 Chilkat Software, Inc. All Rights Reserved.