Javascript Input Numbers

How do you take 2 numbers from the User with window.prompt and add them up without concatenating? What I thought was: var temp = window.prompt('Number1') var temp2 = window.prompt

Solution 1:

You need to convert the values to Number, there are plenty of ways to do it:

var test1 = +window.prompt("Number1"); // unary plus operatorvar test2 = Number(window.prompt("Number2")); // Number constructorvar test3 = parseInt(window.prompt("Number3"), 10); // an integer? parseIntvar test4 = parseFloat(window.prompt("Number4")); // parseFloat

Solution 2:

answer = parseInt(temp) + parseInt(temp2);

is what you're looking for

More information on parseInt: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/parseInt

Solution 3:

You need to explicitly convert them to numbers:

var answer = Number(temp) + Number(temp2);

A somewhat faster alternative is:

var answer = (temp - 0) + (temp2 - 0);

Solution 4:

by default, text from window.prompt is interpreted as string so the + operator concatinates them, you need to parse the values to integers using parseInt

Solution 5:

The problem is that your input is a string (text) and you have to convert it to a number.

You can do that with the parseInt() function or by mixing it with another number.

Examples:

var temp = window.prompt("Number1") * 1;
var temp = parseInt(window.prompt("Number2");