I am a beginner with Javascript/programming and I am trying to make the "demo2" id change with the 5, 10 or 15 variable chosen in the functions (trigger by the buttons), but it keeps showing "0". What do I have to do?
<!DOCTYPE html>
<html>
<body>
<button onclick="alternative1()">5</button>
<button onclick="alternative2()">10</button>
<button onclick="alternative3()">15</button>
<p id="demo"></p>
<p id="demo2"></p>
<script>
var x = 0;
var y = 0;
function alternative1() {y = x + 5;
document.getElementById("demo").innerHTML = "You have chosen " + y;
}
function alternative2() {y = x + 10;
document.getElementById("demo").innerHTML = "You have chosen "+ y;
}
function alternative3() {y = x + 15;
document.getElementById("demo").innerHTML = "You have chosen "+ y;
}
document.getElementById("demo2").innerHTML = y;
</script>
</body>
</html> You can’t access variables declared inside a function from outside a function. The variable belongs to the function’s scope only, not the global scope.
You don't need 3 functions for this. You can do it with 1.
<!DOCTYPE html>
<html>
<body>
<button onclick="alternative(this)">5</button>
<button onclick="alternative(this)">10</button>
<button onclick="alternative(this)">15</button>
<p id="demo"></p>
<script>
function alternative(obj) {
document.getElementById("demo").innerHTML = "You have chosen " + obj.innerHTML;
}
</script>
</body>
</html> Happy learning
It is normal that there is zero because in 'y' there is zero and no operation performed on y.
I hope that this answer will help you to understand what you have done.