I'm new to JavaScript and following a course, I've tried to look for answers on other posts but I couldn't find anything similar, hopefully, I didn't miss any.
I have this code:
const calculateWeight = (earthWeight, planet) => {
if (typeof earthWeight !== "number") {
return "The earth weight must be a number!!";
}
if (typeof planet !== "string") {
return "The planet will accept only letters!!";
}
planet = planet.charAt(0).toUpperCase() + planet.slice(1).toLowerCase();
if (planet === "Mercury") {
return earthWeight * 0.378;
} else if (planet === "Venus") {
return earthWeight * 0.907;
} else if (planet === "Mars") {
return earthWeight * 0.377;
} else if (planet === "Jupiter") {
return earthWeight * 2.36;
} else if (planet === "Saturn") {
return earthWeight * 0.916;
} else {
return "Invalid Planet Entry. Try: Mercury, Venus, Mars, Jupiter, or Saturn."
}
}
console.log(calculateWeight(100, "Jupiter"));On the first and second if statements, I've used the typeof to return a message in case the argument for earthWeight is not a number and the argument for planet is not a string in the very last line of the code where I run the function.
It works if I put a string instead of a number and vice-versa, but if I put a word without quotes, simulating a mistake, I just get an error, is there any way to actually return a message?
Looking at MDN documentation, it seems that a word without quotes should be typeof "undefined" so I thought that changing that code like this, would help:
if (typeof earthWeight !== "number" || typeof earthWeight === "undefined") {
return "The earth weight must be a number!!";
}
if (typeof planet !== "string" || typeof planet === "undefined") {
return "The planet will accept only letters!!";
}Is that something possible?
Kind regards.