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JavaScript

Ziyu Zhang
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Ziyu Zhang
Front End Web Development Techdegree Student 7,739 Points
Posted by Ziyu Zhang
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Ziyu Zhang
Front End Web Development Techdegree Student 7,739 Points

I don't understand why my code doesn't work

Here is my code:

function typeNumber(){
alert("Let's do some math!");
var num1 = prompt("Please type a number");
num1 = parseFloat(num1);
var num2 = prompt("Please type another number");
num2 = parseFloat(num2);
var message;

if(num2 === 0){
  alert('The second number is 0. You can\'t divide by zero. Reload and try again.');
} else if (isNan(num1)){
  alert('At least one of the values you typed is not a number. Reload and try again.');
} else{
  message =`${num1} + ${num2} = ${num1 + num2}`;
  document.write(message);
}

// build an HTML message
typeNumber();
Brandon White
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Brandon White
Full Stack JavaScript Techdegree Graduate 34,662 Points

In what way is your code not working, Ziyu?

Is it not writing anything to the document object at all, or is it not writing what you’re expecting. If it’s the former, you might take a look at the Document.write method on mdn:

https://developer.mozilla.org/en-US/docs/Web/API/Document/write

1 Answer

Thayer Y
Thayer Y
29,789 Points

Hi, You need to fix 2 things

1- instead of (isNan(num1)
make it like this (isNaN(num1)
2- you need one more curly brace } to close your function