Category: JavaScript

Sometimes, we want to define a JavaScript function to get the difference between two numbers.

In this article, we’ll look at how to define a JavaScript function to get the difference between two numbers.

How to define a JavaScript function to get the difference between two numbers?

To define a JavaScript function to get the difference between two numbers, we use the Math.abs function.

For instance, we write

const difference = (a, b) => {
  return Math.abs(a - b);
};

to define the difference function.

In it, we call Math.abs with a - b to get the absolute difference between a and b.

Conclusion

To define a JavaScript function to get the difference between two numbers, we use the Math.abs function.

Sometimes, we want to get the base file name in JavaScript.

In this article, we’ll look at how to get the base file name in JavaScript.

How to get the base file name in JavaScript?

To get the base file name in JavaScript, we can use some string methods.

For instance, we write

const basename = (path) => {
  return path.split("/").reverse()[0];
};

to define the basename function that gets the base file name by calling split with '/' to split the path string into an array of path segment strings.

And then we call reverse to return a reversed version of the array and then use [0] to get the base file name from the path.

Conclusion

To get the base file name in JavaScript, we can use some string methods.

Sometimes, we want to get all the elements of a particular form with JavaScript

In this article, we’ll look at how to get all the elements of a particular form with JavaScript.

How to get all the elements of a particular form with JavaScript?

To get all the elements of a particular form with JavaScript, we use the elements property.

For instance, we write

const formElements = document.getElementById("someFormId").elements;

to select the form element with getElementById.

Then we use the elements property to return a collection with all the elements in the form.

Elements returned includes input, select, textarea and button elements.

Conclusion

To get all the elements of a particular form with JavaScript, we use the elements property.

Sometimes, we want to remove all script tags from HTML with a JavaScript regular expression.

In this article, we’ll look at how to remove all script tags from HTML with a JavaScript regular expression.

How to removing all script tags from HTML with a JavaScript regular expression?

To remove all script tags from HTML with a JavaScript regular expression, we can use a regex that match the script tags and its contents.

For instance, we write

/<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi

to define a regex that matches the script tags and the contents inside.

We use g to find all matches.

And we use i to find matches in a case insensitive manner.

Conclusion

To remove all script tags from HTML with a JavaScript regular expression, we can use a regex that match the script tags and its contents.

Sometimes, we want to filter a JavaScript Map.

In this article, we’ll look at how to filter a JavaScript Map.

How to filter a JavaScript Map?

To filter a JavaScript Map, we convert it to an array.

For instance, we write

const map0 = new Map([
  ["a", 1],
  ["b", 2],
  ["c", 3],
]);

const map1 = new Map([...map0].filter(([k, v]) => v < 3));

console.info([...map1]);

to create a map with the Map constructor.

Then we convert it to an array with the spread operator.

And then we call filter with a function that checks if value v is less than 3.

We use the returned array to create another Map.

Conclusion

To filter a JavaScript Map, we convert it to an array.