使用jQuery在IE11中显示动态内容

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <section id="welcomeNew"> <h1>Welcome to AT&T!</h1> <p>We're so glad you're visiting us for the first time.</p> </section> <section id="welcomeBack"> <h1>Welcome back!</h1> <p>We're so glad you're back!</p> </section>

URL API是 not supported 在IE11中,这意味着这些行将失败并将用户引导到 else {} 条款:

var visitor = new URL(location);
var newvisitor = visitor.searchParams.get("v");

编辑: 下面是一些在硬编码测试中运行的有用的相等性检查。

let newvisitor = 0; // <-- var is fine, too, but not const

console.log('==, testing number 0 against string equality')
if (newvisitor == '0') {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

console.log('==, testing number 0 against numeric equality')
if (newvisitor == 0) {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

newvisitor = "0";

console.log('==, testing string "0" against string equality')
if (newvisitor == '0') {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

console.log('==, testing string "0" against numeric equality')
if (newvisitor == 0) {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

newvisitor = 0;

console.log('===, testing number 0 against string equality')
if (newvisitor === '0') {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

console.log('===, testing number 0 against numeric equality')
if (newvisitor === 0) {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

newvisitor = "0";

console.log('===, testing string "0" against string equality')
if (newvisitor === '0') {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}

console.log('===, testing string "0" against numeric equality')
if (newvisitor === 0) {
  console.log("New visitor.")
} else {
  console.log("Returning visitor.")
}