How to change background colour of an element? It's throwing error

Question

How to change background colour of an element? It's throwing error

-
Uncaught TypeError: Cannot set properties of undefined (setting 'background')
Code -
function changeBg() { document.getElementsByClassName("about-opt").style.background = "#99f";
}

0

09.06.2023

15 ответов

19 просмотров

𝔄𝔐𝔄𝔑 𝔎ℜ Автор вопроса

Malware ( DM = BLOCK )
getElementsByClassName returns a collection of ele...

Yeah, I'm changing bg of multiple items

0

09.06.2023

Malware ( DM = BLOCK )

𝔄𝔐𝔄𝔑 𝔎ℜ
Yeah, I'm changing bg of multiple items

Use changeBg() function

0

09.06.2023

𝔄𝔐𝔄𝔑 𝔎ℜ Автор вопроса

Malware ( DM = BLOCK )
Use changeBg() function

Means?

0

09.06.2023

Malware ( DM = BLOCK )

𝔄𝔐𝔄𝔑 𝔎ℜ
Means?

Do a google search for- changeBg function javascript

0

09.06.2023

Mahdi

Simple: Use loop.Why don't you use adding a class instead of directly applying the style?

0

09.06.2023

Mr Thieves

function changeBackGround(){ //if is one element let element = document.querySelector(".about-opt"); if(element){ element.style.background = "#99f"; } //if is more thnan one element let elements = document.querySelectorAll(".about-opt"); for(let el of elements)[ el.style.background = "#99f"; ] }

0

09.06.2023

Malware ( DM = BLOCK )

Mr Thieves
function changeBackGround(){ //if is one eleme...

Don't spoon feed by sharing the whole code

0

09.06.2023

Mr Thieves

Malware ( DM = BLOCK )
Don't spoon feed by sharing the whole code

why?

0

09.06.2023

Malware ( DM = BLOCK )

Mr Thieves
why?

they won't learn anything

0

09.06.2023

Mr Thieves

Malware ( DM = BLOCK )
they won't learn anything

yes you right.

0

09.06.2023

𝔄𝔐𝔄𝔑 𝔎ℜ Автор вопроса

Mahdi
Simple: Use loop.Why don't you use adding a class ...

I want to change the background colour of elements using onclick of a button: Here is a sample - <button onclick="changeBg()"> This is js code - function changeBg() { document.getElementsByClassName("about-opt").style.background = "#99f"; }

0

10.06.2023

Richard | If you DM for support you PAY

𝔄𝔐𝔄𝔑 𝔎ℜ
I want to change the background colour of elements...

The proper way is to toggle a class on your body element, you css styles then match the body class and element

0

10.06.2023

𝔄𝔐𝔄𝔑 𝔎ℜ Автор вопроса

Richard | If you DM for support you PAY
The proper way is to toggle a class on your body e...

toggle a class by javascript?

0

10.06.2023