我创建了一个 ids 的对象,但是我无法在我的 for 之外或在我的 next .then () 中访问它,我将 det 作为全局变量,有人知道它错在哪里吗?
.then(function(idHome){
home_id = idHome;
var detname_img = [];
var sqlEdit = "INSERT INTO images_det SET ?";
for(var k = 0; k < object.det_img.length; k++){
detname_img.push({
name_img : object.det_img[k].name_img,
});
connection.query(sqlEdit,detname_img[k]);
}
// console.log(detname_img);
for(var i = 0; i < detname_img.length; i++){
var getDet = ("SELECT det_id from images_det where name_img = '" + detname_img[i].name_img + " ' order by 1 desc limit 1");
connection.query(getDet, function(erro, result){
for(var k = 0; k < result.length; k++){
det.push({
det_id : result[k].det_id
});
console.log(chalk.blue(det[0].det_id));
return det;
}
});
}
});
最佳答案
假设您使用 this Node mysql 包你可以从 result 中获取插入的 id插入语句。
由于该包似乎没有意识到 promise 的存在,您可以使用将返回 promise 的包装器清除 api:
//turn an insert query with callback function
// into a function returning a promise
const insertAsPromise = connection => args =>
new Promise(
(resolve,reject)=>
//call connection query with variable amount of argument(s)
// using Function.prototype.apply
connection.query.apply(connection,args.concat(
//add the callback to the list of arguments, callback
// is the last argument
(error, results, fields) =>
(error)
? reject(error)
: resolve([results,fields])
))
);
const sqlEdit = "INSERT INTO images_det SET ?";
Promise.all(
object.det_img.map(
image=>//map magical/global object.det_img to promise
insertAsPromise(connection)([sqlEdit,image.name_img])
.then(//when promise resolves get the inserted id
([results,fields])=>
results.insertId
)
)
)
.then(
results=>console.log(results)//should log an array of id's
)
.catch(
err=>console.error("something went wrong:",err)
)
关于javascript - 我无法在 .then() Promise 中返回对象,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48483312/