我在等待我的 forEach 循环（里面有一个Promise）完成时遇到了问题。我找不到任何真正的解决方案，这会使脚本等到结束，然后再继续执行。我无法使 someFunction 同步。
makeTree: function (arr) {
arr.forEach(function (resource) {
someModule.someFunction(resource).then(function () { //a Promise
//do something with the resource that has been modified with someFunction
});
});
// do something after the loop finishes
}
而不是forEach()使用map()创建的Promise，然后使用数组Promise.all()
let promiseArr = arr.map(function (resource) {
// return the promise to array
return someModule.someFunction(resource).then(function (res) { //a Promise
//do something with the resource that has been modified with someFunction
return res;
})
});
Promise.all(promiseArr).then(function(resultsArray){
// do something after the loop finishes
}).catch(function(err){
// do something when any of the promises in array are rejected
})
试试这个，
makeTree: function (arr) {
var promises = [];
arr.forEach(function(resource) {
promises.push(someModule.someFunction(resource));
});
Promise.all(promises).then(function(responses) {
// responses will come as array of them
// do something after everything finishes
}).catch(function(reason) {
// catch all the errors
console.log(reason);
});
}
您可以通过简单的示例参考此链接以获取更多信息Promise.all。