File upload principle_ Sorting + summary

File upload is a problem we often encounter. The form has a) attribute,

For information about the form, please refer to:,

This property is generally the default value,

That is, the form processes only the values in the form field.

If you want to upload a file, you can set that the form will be processed as a binary stream

Manage the form data and encapsulate the contents of the file specified in the file field into the request parameters.

In the form element, the attribute specifies the content type of the form dataset code passed to the server. Its default value is

The format attribute used for normal data submission has three values

They all belong to type, which can be referred to

: the content of the file cannot be obtained, so the upload cannot be realized.

: get uploaded data

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