Author: John Au-Yeung

Sometimes, we want to configure dynamic routes with Express.js and JavaScript.

In this article, we’ll look at how to configure dynamic routes with Express.js and JavaScript.

How to configure dynamic routes with Express.js and JavaScript?

To configure dynamic routes with Express.js and JavaScript, we can make a route accept URL parameters.

For instance, we write

app.get("/article/:id", (req, res) => {
  res.render("article" + req.params.id);
});

to add the /article/:id route.

:id is the placeholder for the id route parameter.

And we get the value of that from req.params.id.

Conclusion

To configure dynamic routes with Express.js and JavaScript, we can make a route accept URL parameters.

Sometimes, we want to get the immediate first child element with JavaScript.

In this article, we’ll look at how to get the immediate first child element with JavaScript.

How to get the immediate first child element with JavaScript?

To get the immediate first child element with JavaScript, we use the firstChild property.

For instance, we write

console.log(parentElement.firstChild);

to get the first child of the parentElement with parentElement.firstChild.

Conclusion

To get the immediate first child element with JavaScript, we use the firstChild property.

Sometimes, we want to call JavaScript code from a HTML form.

In this article, we’ll look at how to call JavaScript code from a HTML form.

How to call JavaScript code from a HTML form?

To call JavaScript code from a HTML form, we set the action attribute to the JavaScript code we want to run.

For instance, we write

<form action="javascript:handleClick()">...</form>

to set the action attribute to call the handleClick function so it’s called when we submit the form.

Conclusion

To call JavaScript code from a HTML form, we set the action attribute to the JavaScript code we want to run.

Sometimes, we want to write a RGB color value in JavaScript.

In this article, we’ll look at how to write a RGB color value in JavaScript.

How to write a RGB color value in JavaScript?

To write a RGB color value in JavaScript, we set the color to an rgb string.

For instance, we write

parent.childNodes[1].style.color = "rgb(155, 102, 102)";

to set the color property to the color string we want.

Conclusion

To write a RGB color value in JavaScript, we set the color to an rgb string.

Sometimes, we want to clear or remove JavaScript event handler.

In this article, we’ll look at how to clear or remove JavaScript event handler.

How to clear or remove JavaScript event handler?

To clear or remove JavaScript event handler, we can set the event handler property to null.

For instance, we write

document.getElementById("aspnetForm").onsubmit = null;

to select the element with getElementById.

Then we set its onsubmit property to null to remove the submit event handler.

Conclusion

To clear or remove JavaScript event handler, we can set the event handler property to null.