How Can I Create a Simple JavaScript Countdown Timer?

Creating a Simple JavaScript Countdown Timer

Your query about creating a minimalist countdown timer is a common one in web development. Let's break down the steps involved in achieving this.

Vanilla JavaScript Approach:

For your specific requirement of displaying a timer that counts down from "05:00" to "00:00" and resets, you can employ the following approach using vanilla JavaScript:

function startTimer(duration, display) {
    var timer = duration, minutes, seconds;
    setInterval(function () {
        minutes = parseInt(timer / 60, 10);
        seconds = parseInt(timer % 60, 10);

        minutes = minutes < 10 ? "0" + minutes : minutes;
        seconds = seconds < 10 ? "0" + seconds : seconds;

        display.textContent = minutes + ":" + seconds;

        if (--timer < 0) {
            timer = duration;
        }
    }, 1000);
}

window.onload = function () {
    var fiveMinutes = 60 * 5,
        display = document.querySelector('#time');
    startTimer(fiveMinutes, display);
};

In this script:

• duration specifies the initial countdown time in seconds (here, 5 minutes).
• display is an HTML element that will show the countdown.
• setInterval executes the timer logic every second (1000 milliseconds).
• Inside the timer, parseInt is used to convert the remaining time into minutes and seconds.
• The displayed strings are padded with zeros to maintain the "05:00" format.
• When the timer reaches 0, it resets back to duration.

Additional Features:

If desired, you can extend the functionality with features such as a start/stop button:

<button>

document.getElementById("start").addEventListener("click", function () {
    // Start the timer...
});

document.getElementById("stop").addEventListener("click", function () {
    // Stop the timer...
});

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