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React Native

Check if a MIME Entity is multipart/alternative

See more MIME Examples

Demonstrates the Chilkat Mime.IsMultipartAlternative method, which returns whether the Content-Type is exactly multipart/alternative. 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: Recognizing multipart/alternative matters because its children are the same content in different formats — you display one (usually the last renderable), not all of them. That is the opposite of multipart/mixed, where every child is shown.

Chilkat React Native Downloads

React Native
import { Mime } from '@chilkat/react-native'

function chilkatExample() {
  // Demonstrates the Mime.IsMultipartAlternative method, which returns whether the Content-Type is multipart/alternative.  It takes no arguments.

  const mime = new Mime();
  try {
    mime.loadMimeFile('qa_data/multipart_message.eml');
  } catch {
    console.log(mime.lastErrorText);
    return;
  }

  if (mime.isMultipartAlternative()) {
    console.log('This is a multipart/alternative entity.');
  } else {
    console.log('This is not multipart/alternative.');
  }
}