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Uncaught (In Promise) error when rejecting a Promise using setTimeout() in JavaScript

<p>I'm learning Promises in JavaScript and I decided to implement a simple Promise where I would set a timeout of 3 seconds and then reject the Promise. After rejecting it, I catch the error and display it in an HTML element. The promise runs perfectly and displays the message, but I get the following error in the console. </p> <pre class="brush:php;toolbar:false;">Uncaught (in promise) I hate you Promise.then (async) (anonymous)</pre> <p>Here is the code for your reference -</p> <p> <pre class="snippet-code-js lang-js prettyprint-override"><code>const myPromise = new Promise(function(myResolve, reject) { setTimeout(() => { reject('I hate you'); }, 3000); }); myPromise.then(function(value) { document.getElementById("demo").innerHTML = value; }); myPromise.catch( error => { console.log("Catching it"); document.getElementById("demo").innerHTML = error; });</code></pre> <pre class="snippet-code-html lang-html prettyprint-override"><code><h2>JavaScript Promise</h2> <p>Wait 3 seconds (3000 milliseconds) for this page to change.</p> <h1 id="demo"></h1></code></pre> </p> <p>Please help me figure out the mistake I'm making. </p>
P粉139351297P粉139351297515 days ago527

reply all(2)I'll reply

  • P粉748218846

    P粉7482188462023-09-06 12:09:35

    This should work

    <html>

<body>

  <h2>JavaScript Promise</h2>

  <p>Wait 3 seconds (3000 milliseconds) for this page to change.</p>

  <h1 id="demo"></h1>

  <script>
    const myPromise = new Promise(function(myResolve, reject) {
      setTimeout(() => {
        reject('I hate you');
      }, 3000);
    });

    myPromise.then(function(value) {
      document.getElementById("demo").innerHTML = value;
    }).catch(error => {
      console.log("Catching it");
      document.getElementById("demo").innerHTML = error;
    });
  </script>

</body>

</html>

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  • P粉696891871

    P粉6968918712023-09-06 10:15:51

    myPromise.then(function(value) {
  document.getElementById("demo").innerHTML = value;
}).catch( error => {
    console.log("Catching it");
    document.getElementById("demo").innerHTML = error;
});

    You need to catch the error after .then

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    0
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