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JavaScript

Check if a MIME Entity is Multipart

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Demonstrates the Chilkat Mime.IsMultipart method, which returns whether the Content-Type begins with multipart/. It takes no arguments.

Note: The file path is relative to the application's current working directory. Absolute paths may also be used. Supply the path to your own file.

Background: The first question when processing a message is usually whether it is a single part or a container of parts, because that decides whether you read the body directly or iterate children. IsMultipart answers it for any of the multipart subtypes at once; use the more specific predicates when the exact subtype matters.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

//  Demonstrates the Mime.IsMultipart method, which returns whether the Content-Type begins with multipart/.  It takes no arguments.

var mime = new CkMime();
success = mime.LoadMimeFile("qa_data/multipart_message.eml");
if (success == false) {
    console.log(mime.LastErrorText);
    return;
}

if (mime.IsMultipart()) {
    console.log("This is a multipart entity.");
}
else {
    console.log("This is not a multipart entity.");
}