Sometimes, we want to compose multipart/form-data with a different Content-Type on each part with JavaScript.
In this article, we’ll look at how to compose multipart/form-data with a different Content-Type on each part with JavaScript.
How to compose multipart/form-data with a different Content-Type on each part with JavaScript?
To compose multipart/form-data with a different Content-Type on each part with JavaScript, we call the form data append method with a blob.
For instance, we write
const formData = new FormData();
formData.append(
"items",
new Blob(
[
JSON.stringify({
name: "Book",
quantity: "12",
}),
],
{
type: "application/json",
}
)
);
to call formData.append with the key and a blob.
In the blob, we have the JSON content as a string in an array.
And we set the MIME type of the content by setting type to "application/json".
Conclusion
To compose multipart/form-data with a different Content-Type on each part with JavaScript, we call the form data append method with a blob.
