寫法1
let?queryData?=?function?queryData()?{
????return?new?Promise((resolve,?reject)?=>?{
???????
????});
};
let?qu?=?queryData();
qu.then(xxx);寫法2let?queryData?=?new?Promise((resolve,?reject)?=>?{
???????
????});
};
let?qu?=?queryData;
qu.then(xxx);寫法1 和寫法2 有什么區(qū)別? ?為什么要new promise 要放到return里?用意何在?
new Promise為什么要放到return里?
天天向上學(xué)
2019-02-25 23:37:00
