Window: reportError() method
ThereportError()
method of theWindow
interface may be used to report errors to the console or event handlers of global scopes, emulating an uncaught JavaScript exception.
This feature is primarily intended for custom event-dispatching or callback-manipulating libraries.Libraries can use this feature to catch errors in callback code and re-throw them to the top level handler.This ensures that an exception in one callback will not prevent others from being handled, while at the same time ensuring that stack trace information is still readily available for debugging at the top level.
Syntax
reportError(throwable)
Parameters
Return value
None (undefined
).
Exceptions
TypeError
The method is called without an error argument.
Examples
Feature test for the method using:
if (typeof window.reportError === "function") { // function is defined}
The following code shows how you might create and report an error, and how it may be caught using either theonerror
event handler property or by adding a listener for theerror
event.Note that the handler assigned toonerror
must returntrue
to stop the event propagating further.
const newError = new Error("Some error message", "someFile.js", 11);window.reportError(newError);window.onerror = (message, source, lineno, colno, error) => { console.error(`message: ${error.message}, lineno: ${lineno}`); return true;};window.addEventListener("error", (error) => { console.error(error.filename);});// Output// > "message:Some error message, lineno: 11"// > "someFile.js"
Specifications
Specification |
---|
HTML # runtime-script-errors |