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web api event

FileReader: error event

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Available in workers

The error event of the FileReader interface is fired when the read failed due to an error (for example, because the file was not found or not readable).

This event is not cancelable and does not bubble.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("error", (event) => { })

onerror = (event) => { }

Event type

A ProgressEvent. Inherits from Event.

Examples

const fileInput = document.querySelector('input[type="file"]');
const reader = new FileReader();

function handleSelected(e) {
  const selectedFile = fileInput.files[0];
  if (selectedFile) {
    reader.addEventListener("error", () => {
      console.error(`Error occurred reading file: ${selectedFile.name}`);
    });

    reader.addEventListener("load", () => {
      console.log(`File: ${selectedFile.name} read successfully`);
    });

    reader.readAsDataURL(selectedFile);
  }
}

fileInput.addEventListener("change", handleSelected);

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also