Operation not working when using number properties (returns NaN)

问题

What's the problem in using number properties? I'm trying to do a simple calculation involving numbers and it returns NaN.

function test () {
    var that = this;

    this.usersCount = 2;
    this.totalSeeds = 10;

    this.test2 = function () {
        console.log(2/10*100); // 20
        console.log(that.usersCount * that.totalSeeds); // 20
        var percentUsersCount = that.usersCount / that.totalseeds * 100; // also tried parseInt() and Number()
        console.log(percentUsersCount); // NaN -- WHY !?!
    }
}

var test = new test();

test.test2();

var test1 = 2;
var test2 = 10;
var percent = test1 / test2 * 100;
console.log(percent); // 20

Why is percentUsersCount NaN?

http://jsfiddle.net/ht2rv1ea/

Edit: https://www.youtube.com/watch?v=yI6VXlNRrI0

回答1:

You misspelled the name of your variable. Use that.totalSeeds instead of that.totalseeds.

回答2:

You have a typo:

  var percentUsersCount = that.usersCount / that.totalseeds * 100;

Change to

  var percentUsersCount = that.usersCount / that.totalSeeds * 100;

来源：https://stackoverflow.com/questions/32905080/operation-not-working-when-using-number-properties-returns-nan