In then
, you can specify only handler function of an exception by passing null
instead of the first parameter:
promise.then(
null,
function(error) {
console.log(error);
}
);
In this case, it is convenient to use a shortened syntax using the catch
method:
promise.catch(
function(error) {
console.log(error);
}
);
Rewrite the following code via the catch
method:
let promise = new Promise(function(resolve, reject) {
setTimeout(function() {
let isError = false;
if (!isError) {
resolve('success');
} else {
reject(new Error('error'));
}
}, 3000);
});
promise.then(
res => console.log(res),
err => console.log(err.message);
});