1, Form-data:
is the multipart/form-datain the HTTP request, which will process the form into a single message, labeled as a unit, separated by a delimiter. You can upload a key-value pair or upload a file. When the uploaded field is a file, there will be content-type to the table name file type; content-disposition, which is used to describe some information about the field;
Because there is boundary isolation, so multipart/form-data can upload files, you can also upload key value pairs, it takes the method of key-value pairs, so you can upload multiple files.
2, x-www-form-urlencoded:
is application/x-www-from-urlencoded, the data in the form will be converted to a key-value pair, for example, Name=java&age = 23
3. Raw
can upload text in any format, you can upload texts, JSON, XML, HTML, etc.
4. Binary
Equivalent to Content-type:application/octet-stream, from the literal meaning, can only upload binary data, usually used to upload files, because there is no key value, so, can only upload one file at a time.
The difference between Multipart/form-data and x-www-form-urlencoded
Multipart/form-data: can upload files and other binary data, you can also upload form key value pairs, but the final will be converted into a message;
X-www-form-urlencoded: Only key-value pairs can be uploaded, and key-value pairs are spaced apart.
The difference between form-data, x-www-form-urlencoded, raw and binary in postman