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原始資料型別: number, string, boolean, undefined, null, object
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基本型別(簡單型別), 即值型別: number, string, boolean
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復雜型別(參考型別): object
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空型別:undefined, null
存盤空間
值型別的值在哪一塊空間中存盤? 堆疊中存盤 參考型別的值在哪一塊空間中存盤? 物件在堆上存盤, 地址在堆疊上存盤 見下圖：
值型別和參考型別的傳遞
判斷下面的值：
練習1：
var num1 = 10; var num2 = num1; num1 = 20; console.log(num1);//20 console.log(num2);//10
練習2：
var num = 50; function f1(num) { num = 60; console.log(num);//60 } f1(num); //50 console.log(num);//50
練習3：
var num1 = 55; var num2 = 66; function f1(num, num1) { num = 100; num1 = 100; num2 = 100; console.log(num);//100 console.log(num1);//100 console.log(num2);//100 } f1(num1, num2); console.log(num1);//55 console.log(num2);//100 console.log(num);// 報錯
練習4：
function Person(name, age, salary) { this.name = name; this.age = age; this.salary = salary; } function f1(person) { person.name = "ls"; person = new Person("aa", 18, 10); } var p = new Person("zs", 18, 1000); console.log(p.name); //zs f1(p); console.log(p.name); //ls
畫圖理解：
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標籤：JavaScript
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