Category: JavaScript Answers

Sometimes, we want to fix ‘observe’ on ‘MutationObserver’: parameter 1 is not of type ‘Node’ with JavaScript.

In this article, we’ll look at how to fix ‘observe’ on ‘MutationObserver’: parameter 1 is not of type ‘Node’ with JavaScript.

How to fix ‘observe’ on ‘MutationObserver’: parameter 1 is not of type ‘Node’ with JavaScript?

To fix ‘observe’ on ‘MutationObserver’: parameter 1 is not of type ‘Node’ with JavaScript, we should make sure the element we’re observing is available.

For instance, we write

const composeObserver = new MutationObserver(function (mutations) {
  mutations.forEach((mutation) => {
    mutation.addedNodes.forEach((node) => {
      //...
    });
  });
});

const composeBox = document.querySelector(".no");
if (composeBox) {
  const config = { childList: true };
  composeObserver.observe(composeBox, config);
}

to select the element to observer with querySelector.

Then if it’s not null, we call observe to observer the changes in the element.

Conclusion

To fix ‘observe’ on ‘MutationObserver’: parameter 1 is not of type ‘Node’ with JavaScript, we should make sure the element we’re observing is available.

Sometimes, we want to declare an array in JavaScript.

In this article, we’ll look at how to declare an array in JavaScript.

How to declare an array in JavaScript?

To declare an array in JavaScript, we can use the array literal syntax.

For instance, we write

const x = [];
const y = [10];

to declare the empty array x.

And we declare the array y with 10 inside.

Conclusion

To declare an array in JavaScript, we can use the array literal syntax.

Sometimes, we want to wait for element to disappear in Cypress and JavaScript.

In this article, we’ll look at how to wait for element to disappear in Cypress and JavaScript.

How to wait for element to disappear in Cypress and JavaScript?

To wait for element to disappear in Cypress and JavaScript, we call the waitUntil method.

For instance, we write

cy.waitUntil(() => {
  return cy.get("element").should("not.exist");
});

to call waitUntil with a callback that returns the condition that the element with selector element shouldn’t exist.

Conclusioin

To wait for element to disappear in Cypress and JavaScript, we call the waitUntil method.

Sometimes, we want to change the ID of an HTML element with JavaScript

In this article, we’ll look at how to change the ID of an HTML element with JavaScript.

How to change the ID of an HTML element with JavaScript?

To change the ID of an HTML element with JavaScript, we set the id property.

For instance, we write

<p id="one">One</p>

to add a p element.

Then we write

document.getElementById("one").id = "two";

to select the element with getElementById.

And then we set its id property to the new ID.

Conclusion

To change the ID of an HTML element with JavaScript, we set the id property.

Sometimes, we w=ant to execute an exe file using Node.js and JavaScript.

In this article, we’ll look at how to execute an exe file using Node.js and JavaScript.

How to execute an exe file using Node.js and JavaScript?

To execute an exe file using Node.js and JavaScript, we use the child_process module.

For instance, we write

const exec = require("child_process").execFile;

exec("hello.exe", (err, data) => {
  console.log(err);
  console.log(data.toString());
});

to call import execFile and assign it to exec.

Then we call exec with the command string with the exe we want to run.

And we get the output from data.

Conclusion

To execute an exe file using Node.js and JavaScript, we use the child_process module.