how to check div is displaynone or block in javascript with code examples

How to Check if a Div is Displayed or Hidden in JavaScript

When working with HTML and CSS, it is common to have elements on a page that are either displayed or hidden from view. In some cases, you might want to know the current state of an element (whether it is displayed or hidden) to take certain actions in your JavaScript code. For example, you might want to show or hide an element in response to a user interaction, or you might want to perform some action only if an element is visible.

In this article, we will look at how to check if a div is displayed or hidden in JavaScript, using the "display" property of an element.

1. Understanding the "display" Property

The "display" property is a CSS property that defines how an element should be displayed on a web page. It can have several values, including "block", "inline", "none", and others.

• "block" elements take up the full width of their parent container and create a new block formatting context. Examples of block elements include "div", "h1", "p", etc.

• "inline" elements take up only as much space as they need and do not create a new block formatting context. Examples of inline elements include "span", "a", "strong", etc.

• "none" elements are not displayed on the page and do not take up any space.

2. Checking if a Div is Displayed or Hidden

To check if a div is displayed or hidden in JavaScript, you can use the "style" property of the element and retrieve the "display" value.

Here's an example:

const div = document.querySelector("#myDiv");
const display = window.getComputedStyle(div).getPropertyValue("display");

if (display === "none") {
  console.log("The div is hidden");
} else {
  console.log("The div is displayed");
}

In this example, we first select the div element with the id "myDiv" using the "querySelector" method. Then, we use the "getComputedStyle" method to retrieve the computed styles of the element, including the "display" property. Finally, we check the value of the "display" property and log a message to the console indicating whether the div is displayed or hidden.

3. Showing or Hiding a Div

Once you know the current state of an element, you can use JavaScript to show or hide it. To hide a div, you can set its "display" property to "none":

const div = document.querySelector("#myDiv");
div.style.display = "none";

To show a div that was previously hidden, you can set its "display" property back to its original value or to "block":

const div = document.querySelector("#myDiv");
div.style.display = "block";

4. Conclusion

In this article, we have seen how to check if a div is displayed or hidden in JavaScript and how to show or hide it. By using the "display" property, you can easily determine the state of an element and take appropriate actions in your code. This can be especially useful when working with user interfaces and dynamic web pages.

1. Element Visibility and the "visibility" Property

In addition to the "display" property, there is another CSS property called "visibility" that you can use to control the visibility of an element. Unlike "display", which determines whether an element takes up space on the page, "visibility" only affects whether the element is visible or not. When an element has a "visibility" value of "hidden", it is still present in the layout of the page and takes up space, but it is not visible.

To check if an element is visible or hidden using the "visibility" property, you can use the same code as above, but replace "display" with "visibility":

const div = document.querySelector("#myDiv");
const visibility = window.getComputedStyle(div).getPropertyValue("visibility");

if (visibility === "hidden") {
  console.log("The div is hidden");
} else {
  console.log("The div is visible");
}

To hide or show an element using the "visibility" property, you can use the following code:

const div = document.querySelector("#myDiv");
div.style.visibility = "hidden";

// To show the element:
div.style.visibility = "visible";

2. Handling Different Display Values

In some cases, you might want to handle different "display" values differently in your JavaScript code. For example, you might want to show or hide an element differently depending on whether it is a "block" or "inline" element.

You can do this by checking the value of the "display" property and performing different actions based on its value:

const div = document.querySelector("#myDiv");
const display = window.getComputedStyle(div).getPropertyValue("display");

if (display === "none") {
  console.log("The div is hidden");
} else if (display === "block") {
  console.log("The div is a block element");
} else if (display === "inline") {
  console.log("The div is an inline element");
} else {
  console.log("The div has a different display value");
}

3. Hiding and Showing Elements Using Classes

Another way to show or hide elements in JavaScript is by using classes. With this approach, you add or remove a class to an element to change its appearance.

Here's an example of how you can hide an element using a class:

const div = document.querySelector("#myDiv");
div.classList.add("hidden");

And here's an example of how you can show an element using a class:

const div = document.querySelector("#myDiv");
div.classList.remove("hidden");

In this example, we are using the "classList" property to add or remove a class called "hidden" from the element. You would define the styles for the "hidden" class in your CSS to control the appearance of the element:

.hidden {
  display: none;
}

This approach is useful when you want to change the appearance of an element in response to a user interaction or when you have multiple elements that you want to hide or show at the same time.

Popular questions

1. How do I check if a div is hidden or visible using JavaScript?

You can check if a div is hidden or visible using the "display" property in JavaScript. You can use the window.getComputedStyle function to retrieve the value of the "display" property for an element, and then check its value against "none". Here's an example:

const div = document.querySelector("#myDiv");
const display = window.getComputedStyle(div).getPropertyValue("display");

if (display === "none") {
  console.log("The div is hidden");
} else {
  console.log("The div is visible");
}

2. How do I hide a div using JavaScript?

You can hide a div using JavaScript by setting its "display" property to "none". Here's an example:

const div = document.querySelector("#myDiv");
div.style.display = "none";

3. How do I show a div using JavaScript?

You can show a div using JavaScript by setting its "display" property to "block". Here's an example:

const div = document.querySelector("#myDiv");
div.style.display = "block";

4. How do I check the "display" property value for a div using JavaScript?

You can check the "display" property value for a div using JavaScript by using the window.getComputedStyle function. This function returns the computed style for an element, which includes all the CSS styles that have been applied to the element, including any styles that have been inherited from its parent elements.

Here's an example of how you can check the "display" property value for a div:

const div = document.querySelector("#myDiv");
const display = window.getComputedStyle(div).getPropertyValue("display");
console.log(display);

5. Can I use the "visibility" property instead of "display" to hide or show a div?

Yes, you can use the "visibility" property instead of "display" to hide or show a div, but the two properties have different effects. The "display" property determines whether an element takes up space on the page, while the "visibility" property only affects whether the element is visible or not. When an element has a "visibility" value of "hidden", it is still present in the layout of the page and takes up space, but it is not visible. To hide or show an element using the "visibility" property, you can set its value to "hidden" or "visible", respectively.

Tag

JavaScript-DOM