javascript - 在 Node.js 循环中等待 Promise，然后再进入下一个迭代

Question

我在node.js中有以下循环

for (var i in details) {
  if (!details[i].AmntRcvd > 0) {
    res.sendStatus(400);
    return;
  }

  totalReceived += details[i].AmntRcvd;
  UpdateDetail(details[i].PONbr, details[i].LineID).then((results) => {
    console.log(results);
    details[i].QtyOrd = results.QtyOrd;
    details[i].QtyRcvd = results.QtyRcvd;
    details[i].QtyPnding = results.QtyPnding;
    details[i].UnitCost = results.UnitCost;
  }).catch((error) => {
    console.log(error);
  });
}

UpdateDetail 函数返回一个 promise 。在继续循环的下一次迭代之前，如何等待 promise 解决/拒绝。

Answer 1

您可以使用await关键字来解决这个问题。更多信息here

async function main() {
  for (var i in details) {
    if (!details[i].AmntRcvd > 0) {
      res.sendStatus(400);
      return;
    }

    try {
      totalReceived += details[i].AmntRcvd;
      let results = await UpdateDetail(details[i].PONbr, details[i].LineID);
      console.log(results);
      details[i].QtyOrd = results.QtyOrd;
      details[i].QtyRcvd = results.QtyRcvd;
      details[i].QtyPnding = results.QtyPnding;
      details[i].UnitCost = results.UnitCost;
    }
    catch(e) {
      console.log(error);
    }
  }
}