JavaScript 語法
• 資料型態:number,string, boolean
(ex) 0xFF 1.31E-2 NaN ‘Black’ true/false
• typeof()
• 動態語言(不需宣告變數型態)
var x = [5, ‘WebII’]; x[0] x[1]
• null, undefined
• instanceof()
3
4.
JavaScript語法
• function func(){
x = 15; //global
var y = 20; //local
}
• 弱型態語言
var result = ‘5’ – ‘3’
• toString(), valueOf(), parseFloat(), parseInt()
4
5.
Scope Chain
var x= 10;
function outer() {
var y = 20;
function inner() {
var z = 30;
}
}
• __parent__
• Closure(擁有閒置變數的運算式)
5
6.
JavaScript語法
• 運算子
+ -* / -- += != === && || ? : void
• 建立物件
var obj = new Object();
var obj = {};
• Constructor, Properties, Method
Car.color, Car[‘color’], Car.speedUp(30)
var Car = {
color : ‘blue',
speed : 0,
speedUp : speedUp
};
Function speedUp() {
…};
6