Rust

MIME -- Convert Base64 to Binary

See more MIME Examples

Loads MIME containing a base64 body and converts it to binary. This changes the Content-Transfer-Encoding header to "binary", and the body is stored as raw unencoded bytes.

The MIME file initially loaded in this example contains:

Content-Disposition: attachment; filename="starfish20.jpg"
Content-Type: image/jpeg; name="starfish20.jpg"
Content-Transfer-Encoding: base64
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==

After converting, the binary MIME looks like the following. (Note: Loading it into a text editor and saving it will corrupt the binary data by dropping bytes. Non-text binary data CANNOT be handled as if it were text without corruption.)

Rust

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

let mime = chilkat::Mime::new();

if mime.load_mime_file("qa_data/mime/starfish20_base64.mim").is_err() {
    println!("{}", mime.last_error_text());
    return;
}

// Show the MIME.  We can see the body is base64 encoded.
let mime_str = mime.get_mime().unwrap_or_default();
println!("{}", mime_str);

// Change the Content-Transfer-Encoding to "binary"
let _ = mime.set_header_field("Content-Transfer-Encoding", "binary");

// Note: Now that the MIME's body is binary (JPG image data),
// we CANNOT get the MIME as a string.  We can only get it as bytes.

mime_bytes = mime.get_mime_bytes();

// We can save it to a file, and then examine it..
let fac = chilkat::FileAccess::new();
if fac.write_entire_file("qa_data/mime/starfish20_binary.mim", &mime_bytes).is_err() {
    println!("{}", fac.last_error_text());
} else {
    println!("Saved binary MIME.");
}