This is about sending HTML forms: with or without files, and so on
- The object that represent HTML form data.
- Constructor
let formData = new FormData([form]);- if Form is provided, it automatically captures its fields
- Can be used with fetch
- What is happening here is that when the submit button is clicked, it will run a async function, passing in the value of e.
- Then we call a fetch request, specify that we are doing a POST (updating / creating a new source to server) instead of GET (default) and in the body, we specify the values. Here, all we have to do is call body: new FormData(formElem"just a identifier")
formData.append(name, value)– add a form field with the given name and value,formData.append(name, blob, fileName)– add a field as if it were , the third argument fileName sets file name (not form field name), as it were a name of the file in user’s filesystem,formData.set(name, value) and formData.set(name, blob, fileName)are the same as append but the only difference is that they remove all fields with the given name and append a new field so it will make sure it only has one field. With append, it will lead to additional adding of sameName fields.formData.delete(name)– remove the field with the given name,formData.get(name)– get the value of the field with the given name,formData.has(name)– if there exists a field with the given name, returns true, otherwise false