Removing elements by class name?

Question

I have the below code to find elements with their class name:

// Get the element by their class name
var cur_columns = document.getElementsByClassName(\'colu         


        

Answer 1

If you prefer not to use JQuery:

function removeElementsByClass(className){
    var elements = document.getElementsByClassName(className);
    while(elements.length > 0){
        elements[0].parentNode.removeChild(elements[0]);
    }
}

Answer 2

You can you use a simple solution, just change the class, the HTML Collection filter is updated:

var cur_columns = document.getElementsByClassName('column');

for (i in cur_columns) {
   cur_columns[i].className = '';
}

Ref: http://www.w3.org/TR/2011/WD-html5-author-20110705/common-dom-interfaces.html

Answer 3

You can use this syntax: node.parentNode

For example:

someNode = document.getElementById("someId");
someNode.parentNode.removeChild(someNode);

Answer 4

Brett - are you aware that getElementyByClassName support from IE 5.5 to 8 is not there according to quirksmode?. You would be better off following this pattern if you care about cross-browser compatibility:

• Get container element by ID.
• Get needed child elements by tag name.
• Iterate over children, test for matching className property.
• elements[i].parentNode.removeChild(elements[i]) like the other guys said.

Quick example:

var cells = document.getElementById("myTable").getElementsByTagName("td");
var len = cells.length;
for(var i = 0; i < len; i++) {
    if(cells[i].className.toLowerCase() == "column") {
        cells[i].parentNode.removeChild(cells[i]);
    }
}

Here's a quick demo.

EDIT: Here is the fixed version, specific to your markup:

var col_wrapper = document.getElementById("columns").getElementsByTagName("div");

var elementsToRemove = [];
for (var i = 0; i < col_wrapper.length; i++) {
    if (col_wrapper[i].className.toLowerCase() == "column") {
        elementsToRemove.push(col_wrapper[i]);
    }
}
for(var i = 0; i < elementsToRemove.length; i++) {
    elementsToRemove[i].parentNode.removeChild(elementsToRemove[i]);
}

The problem was my fault; when you remove an element from the resulting array of elements, the length changes, so one element gets skipped at each iteration. The solution is to store a reference to each element in a temporary array, then subsequently loop over those, removing each one from the DOM.

Try it here.

Answer 5

The skipping elements bug in this (code from above)

var len = cells.length;
for(var i = 0; i < len; i++) {
    if(cells[i].className.toLowerCase() == "column") {
        cells[i].parentNode.removeChild(cells[i]);
    }
}

can be fixed by just running the loop backwards as follows (so that the temporary array is not needed)

var len = cells.length;
for(var i = len-1; i >-1; i--) {
    if(cells[i].className.toLowerCase() == "column") {
        cells[i].parentNode.removeChild(cells[i]);
   }
}

Answer 6

I prefer using forEach over for/while looping. In order to use it's necessary to convert HTMLCollection to Array first:

Array.from(document.getElementsByClassName("post-text"))
    .forEach(element => element.remove());

Pay attention, it's not necessary the most efficient way. Just much more elegant for me.