javascript - 调用promise API时如何有效地聚合数组？

Question

我想执行一系列getData函数，但前提是要获取数据。然后，我需要将所有结果编译为成对的值数组以返回。

以下代码有效，但我需要对另外7个“if(card.x)...”做类似的处理
有什么更好的方法呢？

async function buildingCard(card) {
    let cardToCreate = []
    try {
        if (card.joke1) {
            // wixData.get returns a promise
            let joke = await wixData.get("jokes", card.joke1).then((results) => {
                cardToCreate.push({ "titleText1": results.title })
            })
        }
        if (card.quote1) {
            let quote = await wixData.get("quotes", card.quote1).then((results) => {
                cardToCreate.push({ "fancyText1": results.title })
            })
        }
        return cardToCreate

    } catch (error) {
        console.log("buildcard error: " + error);
        return error;
    }
} 

Answer 1

您在这里有三件事有所不同:

您正在检查的属性的名称

您传递的字符串get

对象的result属性(这最后看起来很奇怪)

您可以使用这些对象的值定义对象的数组，如下所示:

let props = [
    {name: "joke1", key: "jokes", resultKey: "titleText1"},
    {name: "quote1", key: "quotes", resultKey: "fancyText1"},
    // ...
];

然后，如果要并行查询，则可以使用Promise.all等待多个promise生效，然后从结果数组中推送条目:

async function buildingCard(card) {
    // Define the stuff you'll do
    let props = [
        {name: "joke1", key: "jokes", resultKey: "titleText1"},
        {name: "quote1", key: "quotes", resultKey: "fancyText1"},
        // ...
    ];
    let cardToCreate = [];
    try {
        return Promise.all(props
            // Only the ones with values
            .filter(({name}) => card[name])
            // Map to the object to push
            .map(
                ({name, key, resultKey}) =>
                wixData.get(key).then(results => ({[resultKey]: results}))
            )
        );
    } catch (error) {
        console.log("buildcard error: " + error);
        return error;
    }
}

如果您想一次打一个电话，可以改用for-of循环:

async function buildingCard(card) {
    // Define the stuff you'll do
    let props = [
        {name: "joke1", key: "jokes", resultKey: "titleText1"},
        {name: "quote1", key: "quotes", resultKey: "fancyText1"},
        // ...
    ];
    try {
        let cardToCreate = [];
        for (const {name, key, resultKey} of props) {
            if (card[name]) {
                const results = await wixData.get(key);
                cardToCreate.push({[resultKey]: results});
            }
        }
        return cardToCreate;
    } catch (error) {
        console.log("buildcard error: " + error);
        return error;
    }
}