Category: JavaScript Answers

Sometimes, we want to rename files using Node.js.

In this article, we’ll look at how to rename files using Node.js.

How to rename files using Node.js?

To rename files using Node.js, we can use the fs.rename method.

For instance, we write

const fs = require("fs");

fs.rename("/path/to/Afghanistan.png", "/path/to/AF.png", (err) => {
  if (err) {
    console.log(err);
  }
});

to call fs.rename with the source and destination paths and a callback that runs after rename is done running.

If there’re errors with renaming files, then err is set.

Conclusion

To rename files using Node.js, we can use the fs.rename method.

Sometimes, we want to use an integer as a key in an associative array in JavaScript.

In this article, we’ll look at how to use an integer as a key in an associative array in JavaScript.

How to use an integer as a key in an associative array in JavaScript?

To use an integer as a key in an associative array in JavaScript, we declare a variable as an object.

For instance, we write

const test = {};
test[2300] = 20;
console.log(test["2300"]);

to create the test variable that’s set to an empty object.

Then we add the key 2300 to it and set its value to 20.

The 2300 key will be converted to a string automatically, so we access the value with test["2300"].

Conclusion

To use an integer as a key in an associative array in JavaScript, we declare a variable as an object.

Sometimes, we want to use moment.js to convert date to string in "MM/dd/yyyy" format with JavaScript.

In this article, we’ll look at how to use moment.js to convert date to string in "MM/dd/yyyy" format with JavaScript.

How to use moment.js to convert date to string in "MM/dd/yyyy" format with JavaScript?

To use moment.js to convert date to string in "MM/dd/yyyy" format with JavaScript, we use the format method.

For instance, we write

const startDate = moment().format("MM/DD/YYYY HH:mm:ss");

to create a moment object with moment with the current datetime.

Then we call format with a format string to return a string in MM/dd/yyyy format with the time in hours:minutes:seconds format.

Conclusion

To use moment.js to convert date to string in "MM/dd/yyyy" format with JavaScript, we use the format method.

Sometimes, we want to exclude files from Jest watch with JavaScript.

In this article, we’ll look at how to exclude files from Jest watch with JavaScript.

How to exclude files from Jest watch with JavaScript?

To exclude files from Jest watch with JavaScript, we can add the modulePathIgnorePatterns property into our Jest config.

For instance, in our Jest config, we add

{
  //...
  "modulePathIgnorePatterns": ["directoryNameToIgnore"]
  //...
}

to set the modulePathIgnorePatterns property in our Jest config to an array that has strings of the directories to ignore when running Jest tests.

Conclusion

To exclude files from Jest watch with JavaScript, we can add the modulePathIgnorePatterns property into our Jest config.

Sometimes, we want to get the string representation of a DOM node with JavaScript.

In this article, we’ll look at how to get the string representation of a DOM node with JavaScript.

How to get the string representation of a DOM node with JavaScript?

To get the string representation of a DOM node with JavaScript, we can use the outerHTML property.

For instance, we write

const el = document.createElement("p");
el.appendChild(document.createTextNode("Test"));

const tmp = document.createElement("div");
tmp.appendChild(el);
console.log(tmp.outerHTML);

to create the p element with createElement.

And then we call appendChild to append a text node as its last child to it that we created with createTextNode.

Then we create the tmp element with `createElement.

And then we call tmp.appendChild to append the p element el as the last child of it.

Finally, we get the HTML string version of tmp with tmp.outerHTML.

Conclusion

To get the string representation of a DOM node with JavaScript, we can use the outerHTML property.