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JavaScript

Posted by Alessandro Sebastiani
Alessandro Sebastiani
3,021 Points

+= Does not work in any of the workshop

Somebody could tell me why += operator for add a value in an exist variable does not work? var firstNumber = prompt("Give me the first number"); var firstNumber = parseInt(firstNumber); var secondNumber = prompt('Give me the second number'); var secondNumber = parseInt(secondNumber); var message = '<h1>Math with the number </h1>' + firstNumber + '<h1> and </h1>' + secondNumber; var message += firstNumber + secondNumber;

1 Answer

Ben Slivinn
Ben Slivinn
10,156 Points
Ben Slivinn
Ben Slivinn
10,156 Points 
var firstNumber = prompt("Give me the first number");
var firstNumber = parseInt(firstNumber);
var secondNumber = prompt('Give me the second number');
var secondNumber = parseInt(secondNumber); 
var message = '<h1>Math with the number </h1>' + firstNumber + '<h1> and </h1>' + secondNumber;
var message += firstNumber + secondNumber;

First thing first, please use the Markdown CheatSheet when placing code in treehouse, it's frankly unreadable otherwise.

Answer:

  1. You overwrite the 'message' variable.
  2. Example of using the addition assignment operator (+=):
var message = 1;
message += 5;

output: 6

With strings:

var message = "Hello ";
message += "Alessandro Sebastiani";

output: Hello Alessandro Sebastiani

Note, first i declare the variable, then i use the addition assignment operator on it.

Happy coding!

Alessandro Sebastiani
Alessandro Sebastiani
3,021 Points

Thank you very much ben ^^