className only changing every other class

Question

I\'m performing a small text with JavaScript with the getElementsByClassName() and I am getting some unwanted results. I would like the script to change each CS

Answer 1

This worked for me

var blockSet = document.getElementsByClassName("block-default");
    var blockSetLength = blockSet.length;
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";
 blockSet[0].className = "block-selected";

   

.block-default {
    width: 100px;
    height:50px;
    background-color: green;
    border: 1px solid red;
    padding:10px;
}

.block-selected {
    width: 100px;
    height:50px;
    background-color: blue;
    border: 1px solid white;
    padding:10px;
 }

BLOCK1
BLOCK2
BLOCK3
BLOCK4
BLOCK5
BLOCK6
BLOCK7
BLOCK8