Visual FoxPro

Decode Base64 Image String (GIF, JPG, etc.) and Save to File

I have an XML response that includes a base 64 encoded image string (UPS label). It's a huge string and I need to save it as a gif file on my users pc.

This example shows how to do it..

Visual FoxPro

LOCAL lnSuccess
LOCAL loBd
LOCAL x
LOCAL loXml
LOCAL lcGifBase64

lnSuccess = 0

loBd = CreateObject('Chilkat.BinData')

*  I created an extra-small GIF image for this example..
lnSuccess = loBd.LoadFile("qa_data/gif/xsmall.gif")
IF (lnSuccess <> 1) THEN
    ? "Failed to load GIF image file."
    RELEASE loBd
    CANCEL
ENDIF

*  Show GIF bytes as base64:
? loBd.GetEncoded("base64")

*  This particular GIF in base64 is this:
*  R0lGODlhBQAFAMQAAAAAAP////z8/PHx8evr6+jo6OHh4d7e3sPDw8LCwpqamo2NjWxsbGRkZFpaWk1NTUtLS0hISCwsLCQkJP///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAABQALAAAAAAFAAUAAAUTYCAYQUBAU1lI0TIgztE8jFImIQA7

*  Let's begin with an XML string:
x = "<abc><def>R0lGODlhBQAFAMQAAAAAAP////z8/PHx8evr6+jo6OHh4d7e3sPDw8LCwpqamo2NjWxsbGRkZFpaWk1NTUtLS0hISCwsLCQkJP///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAABQALAAAAAAFAAUAAAUTYCAYQUBAU1lI0TIgztE8jFImIQA7</def></abc>"

loXml = CreateObject('Chilkat.Xml')
lnSuccess = loXml.LoadXml(x)

*  Get the base64 string:
lcGifBase64 = loXml.GetChildContent("def")

? lcGifBase64

*  Load bd with the base64 decoded bytes.  
loBd.Clear()
loBd.AppendEncoded(lcGifBase64,"base64")

*  Save to a GIF file.
lnSuccess = loBd.WriteFile("qa_output/xsmall.gif")

RELEASE loBd
RELEASE loXml