使用數字屬性時操作不起作用（返回NaN）

Question

使用數字屬性時出現什麼問題？我試圖做一個涉及數字的簡單計算，它返回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 

爲什麼percentUsersCount NaN？

http://jsfiddle.net/ht2rv1ea/

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

Answer 1

錯誤拼寫的變量名。使用that.totalSeeds而不是that.totalseeds。

Answer 2

你有一個錯字：

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

更改爲

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