最近,我发现arrayTestundefined =‘某事’和arrayTestnull =‘某事’在javascript中实际上是有效的。看看下面的代码。var arrayTest = [];arrayTest[null] =someUndefinedText is not defined
//arrayTest[someUndefinedText]
我尝试过用import 'core-js/features/string/ends-with'或 if (!String.prototype.endsWith) { if (this_len === undefineddeveloper.mozilla.org/en-US/docs/Web/JavaScript/Reference