The FormData interface provides a way to construct a set of key/value pairs representing form fields and their values, which can be sent using the fetch(), XMLHttpRequest.send() or navigator.sendBeacon() methods. It uses the same format a form would use if the encoding type were set to “multipart/form-data”.

Constructor

• • FormData()

Creates a new FormData object.

Methods

• • FormData.append()

Appends a new value onto an existing key inside a FormData object, or adds the key if it does not already exist.

• • FormData.delete()

Deletes a key/value pair from a FormData object.

• • FormData.entries()

Returns an iterator allowing to go through all key/value pairs contained in this object.

• • FormData.get()

Returns the first value associated with a given key from within a FormData object.

• • FormData.getAll()

Returns an array of all the values associated with a given key from within a FormData.

• • FormData.has()

Returns a boolean stating whether a FormData object contains a certain key.

• • FormData.keys()

Returns an iterator allowing to go through all keys of the key/value pairs contained in this object.

• • FormData.set()

Sets a new value for an existing key inside a FormData object, or adds the key/value if it does not already exist.

• • FormData.values()

Returns an iterator allowing to go through all values contained in this object.

Learn more at MDN Web Docs – FormData.

Get a form action/URL with jQuery:

$('#myForm').attr('action');

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