Rust

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..

Rust

let bd = chilkat::BinData::new();

// I created an extra-small GIF image for this example..
if bd.load_file("qa_data/gif/xsmall.gif").is_err() {
    println!("Failed to load GIF image file.");
    return;
}

// Show GIF bytes as base64:
println!("{}", bd.get_encoded("base64").unwrap_or_default());

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

// Let's begin with an XML string:
let x = "<abc><def>R0lGODlhBQAFAMQAAAAAAP////z8/PHx8evr6+jo6OHh4d7e3sPDw8LCwpqamo2NjWxsbGRkZFpaWk1NTUtLS0hISCwsLCQkJP///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAABQALAAAAAAFAAUAAAUTYCAYQUBAU1lI0TIgztE8jFImIQA7</def></abc>".to_string();

let xml = chilkat::Xml::new();
let _ = xml.load_xml(&x).is_ok();

// Get the base64 string:
let gif_base64 = xml.get_child_content("def").unwrap_or_default();

println!("{}", gif_base64);

// Load bd with the base64 decoded bytes.  
let _ = bd.clear();
let _ = bd.append_encoded(&gif_base64, "base64");

// Save to a GIF file.
let _ = bd.write_file("qa_output/xsmall.gif").is_ok();