manage time

revision:


setTimeout() method

Click the button and wait for 3 seconds.

code:
            <div>
                <p>Click the button and wait for 3 seconds.</p>
                <button onclick="setTimeout(wait, 3000);">press me</button>
                <p id="tijd" style="font-size:1.15vw; color: magenta;"></p>
            </div>
            <style>
                button{position: relative; width: 5vw; height: 2vw; cursor: pointer;}
            </style>
            <script>
                function wait() {
                    var pText = document.getElementById("tijd");
                    pText.innerHTML = "Welcome to this page!";
                }
            </script>
        

clearTimeout() method

Press the first button and wait 4 seconds.

Press the second button before 4 seconds to prevent the first button to execute.

code:
            <div>
                <p>Press the first button and wait 4 seconds.</p>
                <p>Press the second button before 4 seconds to  prevent the first button to execute.</p>
                <button onclick="startFunction()">press me</button>
                <button onclick="stopFunction()">stop</button>
                <p id="tijd2" class="spec" style="font-size:1.15vw; color: red;"></p>
            </div>
            <style>
                button{position: relative; width: 5vw; height: 2vw; cursor: pointer;}
            </style>
            <script>
                var setTimeout_ID;
                function startFunction() {
                    setTimeout_ID = setTimeout(function () {
                        var pText2 = document.getElementById("tijd2");
                        pText2.innerHTML = "Again, welcome  to this page!";
                        }, 4000);
                    }
                function stopFunction() {
                        clearTimeout(setTimeout_ID);
                    }
            </script>
        

setInterval() method

10

code:
        <div>
            <button onclick="counter()">press me</button>
            <h3>10</h3>
        </div>
        <style>
            button{position: relative; width: 5vw; height: 2vw; cursor: pointer;}
        </style>
        <script>
            let count = 10;
            function counter() {
                var h3Heading = document.getElementsByTagName("h3")[0];
                var countDown_ID = setInterval(function () {
                    count--;
                    h3Heading.innerHTML = count;
                    if (count <= 0) {
                    h3Heading.innerHTML = "Welcome to this page!";
                    clearInterval(countDown_ID);
                    }
                }, 1000);
            }
        </script>
    

start timer :

a script on this page starts this clock:

code:
        <div>
            <h3>start timer : </h3>
            <p class="spec">a script on this page starts this clock:</p>
            <p class="spec" id="demo"></p>
        </div>
        <style>
            #demo{position: relative; width: 10vw; height: 2vw; padding: 1vw; border: 0.2vw solid darkgrey; 
                color: blue; background-color: lightgrey;}
        </style>
        <script>
            var myVar = setInterval(myTimer, 1000);
            function myTimer() {
                var d = new Date();
                var t = d.toLocaleTimeString();
                document.getElementById("demo").innerHTML = t;
            }
        </script>
    

stop timer

A script on this page starts this clock:

code:
        <div>
            <h3>stop timer</h3>
            <p>A script on this page starts this clock:</p>
            <button onclick="stop()">stop time</button>
            <p class="spec" id="demo2"></p>
        </div>   
        <style>
            #demo2{position: relative; width: 10vw; height: 2vw; padding: 1vw; border: 0.2vw solid darkgrey; 
                color: blue; background-color: lightgrey;}
        </style>
        <script>
            var Var = setInterval(Timer, 1000);
            function Timer() {
                var d = new Date();
                var t = d.toLocaleTimeString();
                document.getElementById("demo2").innerHTML = t;
            }
            function stop() {
                clearInterval(Var);
            }
        </script>
    

executes setColor()

The setInterval() method executes the setColor() function once every second,
which will toggle between two background colors.


code:
        <div>
            <h3>executes setColor()</h3>
            <p class="spec">The setInterval() method executes the setColor() function once every second, <br>
                which will toggle between two background colors.</p>
            <div id="div1"></div><br>
            <button onclick="stopColor()">stop toggling</button>
        </div>
        <style>
            #div1{width: 30vw; height: 10vw; border:0.5vw outset burlywood;}        
        </style>
        <script>
            const div = document.getElementById("div1")
            var color = setInterval(setColor, 1000);
            function setColor() {
                div.style.backgroundColor = div.style.backgroundColor == "yellow" ? "red" : "yellow";
            }
            function stopColor() {
                clearInterval(color);
        }
        </script>
    

executes move()



this is a div element
code:
        <div>
            <h3>executes move()</h3> 
            <button onclick="move()">move</button><br><br>
            <div id="moveBar">this is a div element</div>
        </div>
        <style>
            #moveBar{background-color: dodgerblue; width: 25%;}
        </style>
        <script>
            function move() {
                var elem = document.getElementById("moveBar");
                var width = 0;
                var idVar = setInterval(change, 10);
    
                function change() {
                    if (width == 100) {
                        clearInterval(idVar)
                    }
                    else {
                        width++;
                        elem.style.width = width + '%';
                    }
                }
            }
        </script>
    

list of coffees - setInterval()

Coffee list:

code:
        <div>
            <h3>list of coffees - setInterval()</h3>
            <p class="spec" style="text-decoration: underline;">Coffee list:</p>
            <ul class="spec" id="coffees"></ul>
        </div>
        <script>
            var ul = document.getElementById("coffees");
    
            let i = 0;
            let coffees = ["Cortado", "Macchiato", "Mocha", "Latte", "Capuccino", "Americano"];
            let numberOfCoffees = coffees.length ;
    
            function iterateOverArray() {
                var li = document.createElement("li");
                li.innerText = coffees[i];
                ul.appendChild(li);
                i++;
            }
    
            var printCoffees = setInterval(iterateOverArray, 1000);
    
            setTimeout(() => {
                clearInterval(printCoffees);
            }, numberOfCoffees * 1001);
        </script>