ReadonlylengthThe length read-only property of the FileList interface returns the number of files in the FileList.
The item() method of the FileList interface returns a File object representing the file at the specified index in the file list.
The
FileListinterface represents an object of this type returned by thefilesproperty of the HTML input element; this lets you access the list of files selected with the<input type='file'>element.MDN Reference