问题描述

我正在尝试编写一个脚本，该脚本需要根据 CSS 选择器找到的特定浏览器对象是否存在来调整其工作流行为.

I'm trying to write a script that needs to adapt it's workflow behavior depending on whether a particular browser object found by CSS selector exists or does not exist.

我不想使用 document.getElementByID 方法，因为这在技术上不是 CSS 选择器，而且我们的整个企业都在 CSS 选择器上进行了标准化，所以除了 CSS 选择器之外的任何遍历 DOM 的东西都不会通过我们的无论如何都要进行代码审查.

I do not want to use a document.getElementByID method as this is not technically a CSS selector, and our entire enterprise is standardized on CSS selector so anything that walks the DOM other then a CSS selector won't make it past our code review process anyway.

var thing = await things.thingSelector(thingName);
if (await t.expect(thing.exists).notOk()) {
   await t.click(things.OpenThing(thingName));
} else {
   return false;
}
return true;

thingSelector 在哪里:

Where thingSelector is:

const thingSelector = name =>
  Selector('p.thing-header-title span')
    .withText(name)
    .parent('div.thing');

OpenThing 在哪里:

Where OpenThing is:

const OpenThing = name =>
    thingSelector(name)
        .find('a.thing-footer-item')
        .withText('Open');

如果对象不存在并且我正在检查它是否存在，或者如果对象存在并且我正在检查它不存在，以及对象存在的情况，我需要能够继续执行不存在，不存在，对象不存在，我正在检查它是否不存在.

I need to be able to continue execution if the object is not there and I'm checking that it exists, or if the object is there and I'm checking that it does not exist, and also the cases where the object is not there and it does not exist and the object is not there and I'm checking that it does not exist.

在所有情况下，我仍然需要继续工作流程.

In all cases I still need to proceed with the workflow.

逻辑硬币的两面我都试过了:

I've tried both sides of the logic coin:

if (!await t.expect(thing.exists).ok())

和

if (await t.expect(thing.exists).notOk())

如果上述其中一项在一种情况下未失败，则在另一种情况下将失败，而在第一个未失败的情况下，另一项将失败.我需要一些能给我逻辑的东西，但永远不会使脚本执行失败，并且仍然允许我根据对象是否存在返回 True 或 False.

If one of the above doesn't fail in one scenario it will fail in the other, and the other one will fail in the scenario that the first one didn't fail. I need something that will give me the logic, but not ever fail the script execution and still allow me to return either True or False depending on if the object is present or not present.

提前感谢您帮助我解决了这个问题，也感谢您学习和提高我的 Javascript 技能！

Thank you in advance for helping me to solve this problem, and also to learn and grow in my Javascript skills!

推荐答案

您可以通过以下方式检查 if 条件中的 async exists 属性:

You can check the async exists property in the if condition in the following way:

if(await things.thingSelector(thingName).exists) {
    // do something 
} 

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