Classic ASP

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..

Chilkat Classic ASP Downloads

Download Chilkat for Classic ASP

Classic ASP

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
success = 0

set bd = Server.CreateObject("Chilkat.BinData")

' I created an extra-small GIF image for this example..
success = bd.LoadFile("qa_data/gif/xsmall.gif")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Failed to load GIF image file.") & "</pre>"
    Response.End
End If

' Show GIF bytes as base64:
Response.Write "<pre>" & Server.HTMLEncode( bd.GetEncoded("base64")) & "</pre>"

' 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>"

set xml = Server.CreateObject("Chilkat.Xml")
success = xml.LoadXml(x)

' Get the base64 string:
gifBase64 = xml.GetChildContent("def")

Response.Write "<pre>" & Server.HTMLEncode( gifBase64) & "</pre>"

' Load bd with the base64 decoded bytes.  
success = bd.Clear()
success = bd.AppendEncoded(gifBase64,"base64")

' Save to a GIF file.
success = bd.WriteFile("qa_output/xsmall.gif")

%>
</body>
</html>