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General Discussion

Aryaman Dhingra
Aryaman Dhingra
3,536 Points
Posted by Aryaman Dhingra
Aryaman Dhingra
3,536 Points

How to change background color with JS

I have some test code here, in which I am trying to change the background color of a page with the click of a button. The code seems correct to me but I don't know where I am going wrong, as the color is not changing. Here is the code.

<body>
        <div>
            <input type='submit' id='red' class='buttons' value='Red'>
            <input type='submit' id='blue' class='buttons' value='Blue'>
            <input type='submit' id='green' class='buttons' value='Green'>
            <input type='submit' id='purple' class='buttons' value='Purple'>
        </div>
        <script>
            var blue = document.querySelector('#blue');
            var red = document.querySelector('#red');
            var green = document.querySelector('#green');
            var purple = document.querySelector('#purple');



            blue.addEventListener('click', => {
                document.body.style.backgroundColor = 'blue';
                                  });
            red.addEventListener('click', => {
                document.body.style.backgroundColor = 'red';
                                 });
            green.addEventListener('click', => {
                document.body.style.backgroundColor = 'green';
                                 });
            purple.addEventListener('click', => {
               document.body.style.backgroundColor = 'green';                      
                                 });

        </script>
    </body>

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The issue is your arrow functions. When you create an arrow function that does not take any parameters you need to have empty parenthesis before the fat arrow. You can't just leave them off like you have done in your code.

Like this:

<body>
        <div>
            <input type='submit' id='red' class='buttons' value='Red'>
            <input type='submit' id='blue' class='buttons' value='Blue'>
            <input type='submit' id='green' class='buttons' value='Green'>
            <input type='submit' id='purple' class='buttons' value='Purple'>
        </div>
        <script>
            var blue = document.querySelector('#blue');
            var red = document.querySelector('#red');
            var green = document.querySelector('#green');
            var purple = document.querySelector('#purple');



            blue.addEventListener('click', () => {
                document.body.style.backgroundColor = 'blue';
                                  });
            red.addEventListener('click', () => {
                document.body.style.backgroundColor = 'red';
                                 });
            green.addEventListener('click', () => {
                document.body.style.backgroundColor = 'green';
                                 });
            purple.addEventListener('click', () => {
               document.body.style.backgroundColor = 'purple';                      
                                 });

        </script>
    </body>

I also changed the color assignment value for the purple button, which you had forgotten to do in your code.

Aryaman Dhingra
Aryaman Dhingra
3,536 Points
Aryaman Dhingra
Aryaman Dhingra
3,536 Points

Thank you!! It works like a charm now!!