Button Confirm

<!DOCTYPE html>
<html>
<body>

<p>Click the button to display a confirm box.</p>

</body>
</html>

***************************************************************************

var txt;
var r = confirm("Press a button!");
if (r == true) {
    txt = "You pressed OK!";
} else {
    txt = "You pressed Cancel!";
}

***************************************

<!DOCTYPE html>
<html>
<body>

<p>Click the button to demonstrate line-breaks in a confirm box.</p>

</body>
</html>

<!DOCTYPE html>
<html>
<body>

<p>Click the button to display a confirm box.</p>

<button onclick="myFunction()">Try it</button>

<script>
function myFunction() {
confirm("Press a button!");
}
</script>

</body>
</html>

***************************************************************************

var txt;
var r = confirm("Press a button!");
if (r == true) {
txt = "You pressed OK!";
} else {
txt = "You pressed Cancel!";
}

***************************************

<!DOCTYPE html>
<html>
<body>

<p>Click the button to demonstrate line-breaks in a confirm box.</p>

<button onclick="myFunction()">Try it</button>

<p id="demo"></p>

<script>
function myFunction() {
var txt;
var r = confirm("Press a button!\nEither OK or Cancel.\nThe button you pressed will be displayed in the result window.");
if (r == true) {
txt = "You pressed OK!";
} else {
txt = "You pressed Cancel!";
}
document.getElementById("demo").innerHTML = txt;
}
</script>

</body>
</html>