DataTransfer: files property

The files read-only property of DataTransfer objects is a list of the files in the drag operation. If the operation includes no files, the list is empty.

This feature can be used to drag files from a user's desktop to the browser.

Note: The files property of DataTransfer objects can only be accessed from within the drop and paste events. For all other events, the files property will be empty — because its underlying data store will be in a protected mode.

Value

A FileList of the files in a drag operation, one list item for each file in the operation. If the drag operation had no files, the list is empty.

Examples

undefined

Reading the files list

This example creates a basic area that you can drop files into and displays some metadata.

html

<pre id="output">Drop files here from your file system.</pre>

css

#output {
  min-height: 200px;
  border: 1px solid black;
  padding: 1em;
}

const output = document.getElementById("output");

function log(text) {
  output.innerText += text;
}

output.addEventListener("dragenter", (e) => {
  e.stopPropagation();
  e.preventDefault();
  output.textContent = "";
});
output.addEventListener("dragover", (e) => {
  e.stopPropagation();
  e.preventDefault();
});
output.addEventListener("drop", (e) => {
  e.stopPropagation();
  e.preventDefault();
  const files = event.dataTransfer.files;
  log(`File Count: ${files.length}\n`);

  for (const file of files) {
    log(`  File: ${file}, ${file.name}, ${file.size} bytes\n`);
  }
});

Specifications

HTML