What is the role of Content-Type?

Content-Type The entity header is used to indicate the MIME type media type of the resource.

In the response, the Content-Type header tells the client the content type of the actual content returned. Browsers perform MIME lookups in some cases and do not necessarily honor the value of this header; to prevent this behavior, the header X-Content-Type-Options can be set to nosniff.

In the request (such as POST or PUT), the client tells the server the type of data actually sent.

Syntax:

Content-Type: text/html; charset=utf-8
Content-Type: multipart/form-data; boundary=something

Directions:

media-type

The MIME type of the resource or data.

charset

Character encoding standard.

boundary

A boundary is required for multipart entities, which consists of 1 to 70 characters from a set of characters known to be very robust through email gateways, rather than ending in whitespace. It is used to encapsulate the boundaries of multiple parts of a message.

Example

##Content-Type in HTML form

In the POST request generated by submitting the HTML form, request The Content-Type of the header is specified by the enctype attribute on the

element

<form action="/" method="post" enctype="multipart/form-data">
  <input type="text" name="description" value="some text">
  <input type="file" name="myFile">
  <button type="submit">Submit</button></form>

The request header looks like this (some headers are omitted here):

POST /foo HTTP/1.1
Content-Length: 68137
Content-Type: multipart/form-data; boundary=---------------------------974767299852498929531610575

---------------------------974767299852498929531610575
Content-Disposition: form-data; name="description" 

some text
---------------------------974767299852498929531610575
Content-Disposition: form-data; name="myFile"; filename="foo.txt" 
Content-Type: text/plain 

(content of the uploaded file foo.txt)
---------------------------974767299852498929531610575

Browser compatibility

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