case user.length < 4; console.log("nametoo short :("); break; Why doesn't this work?

Question

I'm working on switch statements and I've been trying to make this code right here work, but it doesn't seem to output the correct console.log case string.

var user = prompt("What is your name?").toLowerCase();
switch(user){
    case "luka":
    console.log("What a beautiful name, my name is exactly the same :) Hi Luka! :D");
    break;

    case user.length > 10:
    console.log("That's a long name!");
    break;

    case user.length < 4:
    console.log("Not to be rude or impolite to you in any way, but your name is kinda       short :( Not that it isn't cool or something :D");
    break;

}

I've tried putting paranthesis around the user like this (user).length < 4, but that doesn't work, nor some of my other tries. Does anybody know how to implement this correctly?

Answer 1

There is one possible workaround for using switch in the cases like yours:

var user = prompt("What is your name?").toLowerCase();
switch (true) {
    case (user === "luka"):
        console.log("What a beautiful name, my name is exactly the same :) Hi Luka! :D");
        break;

    case (user.length > 10):
        console.log("That's a long name!");
        break;

    case (user.length < 4):
        console.log("Not to be rude or impolite to you in any way, but your name is kinda       short :( Not that it isn't cool or something :D");
}

However I'd follow @epascarello's advice and use if/else blocks.

Answer 2

You should not use conditionals in a switch statement.

Use if/else if

var user = prompt("What is your name?").toLowerCase();
if (user==="luka") {
    console.log("What a beautiful name, my name is exactly the same :) Hi Luka! :D");
} else if (user.length > 10) {
    console.log("That's a long name!");
} else if (user.length < 4) {
    console.log("Not to be rude or impolite to you in any way, but your name is kinda       short :( Not that it isn't cool or something :D");
} else {
    console.log("in else");
}

Answer 3

That's just not how JavaScript switch statements work. The values in the "case" expressions are compared to the value of the switch expression.

The statement you have there is equivalent to:

if (user === "luka") {
    console.log("What a beautiful name, my name is exactly the same :) Hi Luka! :D");
}
else if (user === (user.length > 10)) {
    console.log("That's a long name!");
}
else if (user === (user.length < 4)) {
    console.log("Not to be rude or impolite to you in any way, but your name is kinda       short :( Not that it isn't cool or something :D");    
}

Thus, you're comparing the value of "user" to the results of comparing user.length to those values. Those comparison results are boolean, so "use" will never be === to them.