Visual FoxPro

Download Photo to a File

See more Facebook Examples

Assuming we have the ID of a Photo, this example demonstrates how to download the photo image data to a file. Visual FoxPro

LOCAL lnSuccess
LOCAL loOauth2
LOCAL loRest
LOCAL lcPhotoId
LOCAL loSbPath
LOCAL lcResponseJson
LOCAL loJson
LOCAL lcImageUrl
LOCAL loSbImageUrl
LOCAL loSbToPath
LOCAL lnBCaseSensitive
LOCAL loHttp

lnSuccess = 0

* 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
loOauth2 = CreateObject('Chilkat.OAuth2')
loOauth2.AccessToken = "FACEBOOK-ACCESS-TOKEN"

loRest = CreateObject('Chilkat.Rest')

* Connect to Facebook...
lnSuccess = loRest.Connect("graph.facebook.com",443,1,1)
IF (lnSuccess <> 1) THEN
    ? loRest.LastErrorText
    RELEASE loOauth2
    RELEASE loRest
    CANCEL
ENDIF

* Provide the authentication credentials (i.e. the access key)
loRest.SetAuthOAuth2(loOauth2)

* Assumes we've already obtained a Photo ID.
lcPhotoId = "10210199026347451"

loSbPath = CreateObject('Chilkat.StringBuilder')
loSbPath.Append("/v2.7/")
loSbPath.Append(lcPhotoId)

* First we're going to get the photo informaton so we can get the URL of the image file data.
* Select the fields we want.
* See https://developers.facebook.com/docs/graph-api/reference/photo/
loRest.AddQueryParam("fields","id,album,images")

lcResponseJson = loRest.FullRequestNoBody("GET",loSbPath.GetAsString())
IF (loRest.LastMethodSuccess <> 1) THEN
    ? loRest.LastErrorText
    RELEASE loOauth2
    RELEASE loRest
    RELEASE loSbPath
    CANCEL
ENDIF

loJson = CreateObject('Chilkat.JsonObject')
loJson.EmitCompact = 0
loJson.Load(lcResponseJson)

* Show the JSON in human-readable format.
? loJson.Emit()

* Get the image URL.
lcImageUrl = loJson.StringOf("images[0].source")
? "Downloading from " + lcImageUrl

loSbImageUrl = CreateObject('Chilkat.StringBuilder')
loSbImageUrl.Append(lcImageUrl)

* Build the output local file path.
loSbToPath = CreateObject('Chilkat.StringBuilder')
loSbToPath.Append("qa_output/fb")
loSbToPath.Append(loJson.StringOf("id"))
lnBCaseSensitive = 0
IF (loSbImageUrl.Contains(".jpg",lnBCaseSensitive) = 1) THEN
    loSbToPath.Append(".jpg")
ELSE
    loSbToPath.Append(".png")
ENDIF

? "Downloading to " + loSbToPath.GetAsString()

* Download using Chilkat HTTP.
loHttp = CreateObject('Chilkat.Http')
lnSuccess = loHttp.Download(lcImageUrl,loSbToPath.GetAsString())
IF (lnSuccess <> 1) THEN
    ? loHttp.LastErrorText
ELSE
    ? "Downloaded."
ENDIF

RELEASE loOauth2
RELEASE loRest
RELEASE loSbPath
RELEASE loJson
RELEASE loSbImageUrl
RELEASE loSbToPath
RELEASE loHttp