How Can I Efficiently Get the Value of a Selected Radio Button in JavaScript?

Accessing Radio Button Values: A More Concise Approach

In your JavaScript program, you encountered an issue where the selected radio button's value was returning undefined. The code you provided relies on a loop through aNodeList, which can be inefficient. A more modern and concise way to retrieve the value is through Element querying methods.

Improved Code:

To resolve this issue, consider utilizing the following code:

document.querySelector('input[name="genderS"]:checked').value;

This line accomplishes the same functionality as your loop but in a single line. It leverages the querySelector() method to select the radio button with the specified name attribute ("genderS") and checked status.

How it Works:

• document.querySelector() selects the first matching element in the document that satisfies the specified selector.
• 'input[name="genderS"]' is the selector to match input elements with the name attribute "genderS".
• ':checked' selects only the radio button within that set that is checked.
• The .value property of this element returns the selected value.

Advantages:

• Simplicity: This approach uses a single line of code, making it easier to understand and maintain.
• Efficiency: It avoids the need for a loop, which can improve performance, especially for radio buttons with many options.
• Compatibility: It works with modern browsers, ensuring cross-browser compatibility.

Usage:

You can assign the selected value to a variable as follows:

var genderValue = document.querySelector('input[name="genderS"]:checked').value;

This variable can then be used in your submitForm function or any other part of your program.

By implementing this more concise and efficient method, you can effectively retrieve the selected radio button's value without encountering undefined issues.

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