How to Handle Both Check and Uncheck Events for Radio Buttons in JavaScript?

OnChange Event for Radio Buttons: Handling Check and Uncheck Events

When working with radio buttons, it's essential to handle both check and uncheck events effectively. The standard onChange event doesn't cater to this, as it only triggers when a radio button is selected. This leaves a gap in identifying when a previous selection is deselected.

Workaround for OnChange Event:

Consider the following code snippet:

<code class="js">var rad = document.myForm.myRadios;
var prev = null;
for (var i = 0; i < rad.length; i++) {
    rad[i].addEventListener('change', function() {
        (prev) ? console.log(prev.value): null;
        if (this !== prev) {
            prev = this;
        }
        console.log(this.value)
    });
}</code>

This script accomplishes the desired behavior:

1. It iterates over all radio buttons.
2. For each radio button, an event listener is added to the onChange event.
3. When a radio button is checked, it logs the value of the previously checked radio button (if there was one) and updates the reference to the currently checked radio button.

This solution captures both check and uncheck events, allowing you to access both the previously and currently checked radio buttons' values.

Limitations of OnClick Event:

The onClick event, while more consistent across browsers, still doesn't address the issue of capturing uncheck events. Hence, while it may be considered for certain use cases, it's not a complete solution for handling both check and uncheck events with radio buttons.

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