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javascript - Switch Statement, it does not work with prompt

I just learned switch statements. I was practicing it by building something. When i set the value of variable to a number it works but when i asks the user for a number it always outputs the default statement.

It works with this code:

confirm("You want to learn basic counting?");
var i = 0;
switch (i) {
    case 0:
        console.log(i);
        i++
    case 1:
        console.log(i);
        i++;
    case 2:
        console.log(i);
        i++;
    case 3:
        console.log(i);
        i++;
    case 4:
        console.log(i);
        i++;
    case 5:
        console.log(i);
        i++;
    case 6:
        console.log(i);
        i++;
    case 7:
        console.log(i);
        i++;
    case 8:
        console.log(i);
        i++;
    case 9:
        console.log(i);
        i++;
    case 10:
        console.log(i);
        console.log("Congratulations!");
        break;
    default:
        console.log("Buzz, wronghh");
        break;
}

But when i asks value from user, it dosen't work. Code below doesn't work:

confirm("You want to learn basic counting?");
var i = prompt("Type any number from where you want to start counting[Between 0 and 10]");
switch (i) {
    case 0:
        console.log(i);
        i++
    case 1:
        console.log(i);
        i++;
    case 2:
        console.log(i);
        i++;
    case 3:
        console.log(i);
        i++;
    case 4:
        console.log(i);
        i++;
    case 5:
        console.log(i);
        i++;
    case 6:
        console.log(i);
        i++;
    case 7:
        console.log(i);
        i++;
    case 8:
        console.log(i);
        i++;
    case 9:
        console.log(i);
        i++;
    case 10:
        console.log(i);
        console.log("Congratulations!");
        break;
    default:
        console.log("Buzz, wronghh");
        break;
}
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1 Reply

0 votes
by (71.8m points)

You need to convert the user input from a string to an integer, like so

confirm("You want to learn basic counting?");
var i = prompt("Type any number from where you want to start counting[Between 0 and 10]");
i = parseInt(i); // this makes it an integer
switch(i) {
//...

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