我正在编写一个脚本，我想知道如何优雅地告诉 JS 不要在意某个元素是否缺失，而且肯定不会出错，特别是当它们是已知未知的时候。

前提： 创建一个自动通知脚本，如果州立酒类商店有我指定的酒类库存（buffalo trace 看着你）。官方酒类网站（VABC）没有这个功能。

该网站始终显示您最喜欢的商店（硬编码），但它只会显示接下来的 5 家商店 如果他们有库存 。如果您在您想要的酒类的产品页面上，并且您周围的商店有库存，它们就会显示出来。但如果只有 3 家商店有库存，则只会显示 3 家。如果您周围都没有库存，则不会显示任何库存。问题是我不知道哪些产品（我正在寻找几种）或哪些商店（再次，最喜欢的 +5）有库存。因此每次我都必须声明相同的变量集。

如果说某个产品没有商店 3-5，我希望 Javascript 能够继续前进。现在我收到错误“ 错误：无法在带有选择器“(​​//td[contains(@data-title,'Miles')])[2]”的元素上调用 getText，因为未找到元素” 。脚本期望商店 2（又名“Miles”）存在，但由于没有库存，因此此页面上没有商店。

我尝试将此 Store2Miles.getText() 调用隐藏在 IsExisting = True 门后面，但系统仍然会抛出此错误。结果是脚本/站点只是坐在那里等待超时。由于它在多个页面上执行此操作，这使得脚本运行的时间比应有的时间长得多。就像我说的，我想要一个优雅的解决方案。

代码：

    it(Product1, ()=> {
        browser.url(Product1_URL)
        console.log(Product1)

        let MoreStores = $("(//a[contains(@class,'more-stores')])[1]")
        MoreStores.waitForClickable(500)
        MoreStores.click()

        /*
This section contains the amount of product at my favorite store, and the Address, Miles, and 
        Amount of each of the 5 stores. Since I have no idea how much stock will be of each product, I 
        have to send this complete set to all product pages.
*/

        let MyStoreAmount = $("(//td[contains(@data-title,'Inventory')])[1]")
        let Store2Address = $("(//td[contains(@data-title,'Store')])[2]")
        let Store2Miles = $("(//td[contains(@data-title,'Miles')])[2]")
        let Store2Amount = $("(//td[contains(@data-title,'Inventory')])[2]")
        let Store3Address = $("(//td[contains(@data-title,'Store')])[3]") 
        let Store3Miles = $("(//td[contains(@data-title,'Miles')])[3]")
        let Store3Amount = $("(//td[contains(@data-title,'Inventory')])[3]")
        let Store4Address = $("(//td[contains(@data-title,'Store')])[4]") 
        let Store4Miles = $("(//td[contains(@data-title,'Miles')])[4]")
        let Store4Amount = $("(//td[contains(@data-title,'Inventory')])[4]")
        let Store5Address = $("(//td[contains(@data-title,'Store')])[5]") 
        let Store5Miles = $("(//td[contains(@data-title,'Miles')])[5]")
        let Store5Amount = $("(//td[contains(@data-title,'Inventory')])[5]")
        let Store6Address = $("(//td[contains(@data-title,'Store')])[6]") 
        let Store6Miles = $("(//td[contains(@data-title,'Miles')])[6]")
        let Store6Amount = $("(//td[contains(@data-title,'Inventory')])[6]")

        /*
This section is me creating boolean variables of if Stores are Existing (meaning they have 
        stock) and if they are Nearby. I only care about stores that are stocked and close to me. A 
         stocked store 100 miles away is useless, as is a local store that is empty. I am trying to do 
        IsExisting flags first so that the getText() code wouldn't be read (and thus error) if the store 
        didn't exist first. */

        let MyStoreStocked = false
        let Store2Existing = false
        let Store3Existing = false
        let Store4Existing = false
        let Store5Existing = false
        let Store6Existing = false

        let Store2Nearby = false
        let Store3Nearby = false
        let Store4Nearby = false
        let Store5Nearby = false
        let Store6Nearby = false

        /*
This creates a T/F flag of if your store is stocked with the product you specified
*/
        if (MyStoreAmount.getText() > 0){MyStoreStocked = true} else {MyStoreStocked = false}
        

        /*
This creates T/F flag of if your store exists on the product page. If it doesn't exist, then it 
        has 0 stock. However just because it exists doesn't mean it's close by, it could be 300 miles 
        away.*/

        if (Store2Address.isExisting()){Store2Existing = true} else{Store2Existing = false}
        if (Store3Address.isExisting()){Store3Existing = true} else{Store3Existing = false}
        if (Store4Address.isExisting()){Store4Existing = true} else{Store4Existing = false}
        if (Store5Address.isExisting()){Store5Existing = true} else{Store5Existing = false}
        if (Store6Address.isExisting()){Store6Existing = true} else{Store6Existing = false}
        
        
        /*
I know due to Debugging that this is the exact spot that errors occur.** The first line, the 
        Store2Miles.getText(), even though I tried hiding it behind an If isExisting=True, the system 
        always throws an error on it. It is saying that this element wasn't found. I KNOW some of these 
        won't be found, that's why I put the isExisting gate there. But the system still reads it 
        anyways, and timesout. These timeouts make the whole script run longer. 
]*/

        if (Store2Existing = true){if (Store2Miles.getText() <= Product1_Distance) {Store2Nearby = true} else {Store2Nearby = false}} else {}
        if (Store3Existing = true){if (Store3Miles.getText() <= Product1_Distance) {Store3Nearby = true} else {Store3Nearby = false}} else {}
        if (Store4Existing = true){if (Store4Miles.getText() <= Product1_Distance) {Store4Nearby = true} else {Store4Nearby = false}} else {}
        if (Store5Existing = true){if (Store5Miles.getText() <= Product1_Distance) {Store5Nearby = true} else {Store5Nearby = false}} else {}
        if (Store6Existing = true){if (Store6Miles.getText() <= Product1_Distance) {Store6Nearby = true} else {Store6Nearby = false}} else {}