捕获混合内容错误

Question

I'm trying to detect an XHR failing on mixed content. It looks like different browsers have different implementations:

var xhr = new XMLHttpRequest();
try {
  xhr.open('http://otherdomain/');
} catch (err) {
  console.log(err); // IE10 hits this one
}
try {
  xhr.send(); // Chrome fails here, but doesn't throw an error
} catch (err) {
  console.log(err); // No browser I've tried hits this one
}

I don't want to use autodetection ( xhr.open('//otherdomain') ), since the target might not support http, or https. I simply want to know the call failed, so I can show an error in my page. Is it possible to handle this correctly for all browsers?

Answer 1

There is no way to handle this error with javascript unfortunately. It is a security restriction enforced by the browser and thrown on a lower level. I have tried so many different methods, including the use of extensions but nothing worked except a timeout handler to be honest.