如何选择具有相同类名的 javaScript 中的所有类？

Question

Can you please help me with this to solve out? the bg-color with the 1st div is only changing but the rest is not working help me to solve this!

 const hexNum = [0,1,2,3,4,5,6,7,8,'A','B','C','D','E','F']; const hexBtn = document.querySelector('.btn-hex'); const bgPale = document.querySelector('.bg-color'); const hexCode = document.querySelector('.color-code'); hexBtn.addEventListener('click', getNewHex); function getNewHex(){ let newHexCode = '#'; for (let i = 0; i<6; i++){ let randomHex = Math.floor(Math.random()*hexNum.length); newHexCode +=hexNum[randomHex]; //console.log(newHexCode); } bgPale.style.backgroundColor = newHexCode; hexCode.innerHTML = newHexCode }

 <div class="bg-color palette-1"></div> <div class="bg-color palette-2"></div> <div class="bg-color palette-3"></div>

Answer 1

The issue here is that you are using document.querySelector('.bg-color') which returns the first Element within the document that matches the specified selector, or group of selectors. You need to actually use here document.querySelectorAll('.bg-color') instead as it returns a NodeList representing a list of the document's elements that match the specified group of selectors. Then you will also need to loop through each of the node to change the style like:

const bgPale = document.querySelectorAll('.bg-color')
bgPale.forEach(el => el.style.backgroundColor = newHexCode);

For more info:

• document.querySelector(selectors)
• document.querySelectorAll(selectors)