Why Does `this.style[property]` Sometimes Return an Empty String in JavaScript?

Why Does 'this.style[property]' Return an Empty String?

In a JavaScript program, accessing the 'this.style[property]' property may result in an empty string. This can occur when trying to retrieve the value of a style that was set in a CSS stylesheet.

The 'this.style[property]' property is designed to access inline styles, which are styles that are set directly to an HTML element using the 'style' attribute. It does not fetch styles defined in external or embedded CSS stylesheets.

To resolve this, employ the getComputedStyle() function. This function computes the combined styles of an element, including those defined by stylesheets:

const element = document.getElementById('myId');
const style = getComputedStyle(element);
console.log(style.height); // "100px"

In this example, the 'getComputedStyle()' function is used to retrieve the 'height' property of the element. The console will output the value "100px," which represents the height defined in the stylesheet.

Therefore, 'this.style[property]', while useful for accessing inline styles, is not suitable for getting styles defined in CSS stylesheets. Utilize 'getComputedStyle()' to retrieve the effective style of an element, encompassing all sources.

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