var task1 = new Promise(function(resolve, reject){
resolve("success");
});
var task2 = new Promise(function(resolve, reject){
reject("error");
});
task1.then(task2)
.catch(function(error) {
console.log("catched:", error);
});task1.then(function () {
return task2
})
.catch(function(error) {
console.log('catched:', error);
}); . Then is a function, and task2 is a Promise object, so you must not catch later
because you task2 this promise throws an error but does not have catch function to capture it, if task1 and task2
the promise of reject must follow catch to catch the failure, otherwise it will report an error
var task2 = new Promise(function(resolve, reject){
reject('error');
}).catch(function(error) {
console.log('catched:', error);
});this is also possible
add that if your task runs in parallel and has no dependencies, you should use Promise.all
var jobs = [];
var task1 = new Promise(function(resolve, reject){
resolve('success');
});
var task2 = new Promise(function(resolve, reject){
reject('error');
});
jobs.push(task1);
jobs.push(task2);
Promise.all(jobs).catch(function(error) {
console.log('catched:', error);
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