簡單介紹JavaScript變數範圍
- 17. 套崁函式
var a = 100;
function run() {
var b = 200;
function todo() {
console.log(b);
}
todo();
console.log(a);
}
run();
- 18. 套崁函式
var a = 100;
function run() {
var b = 200;
function todo() {
console.log(b); //200
}
todo();
console.log(a);
}
run();
- 19. 套崁函式
var a = 100;
function run() {
var b = 200;
function todo() {
console.log(b); //200
}
todo();
console.log(a); //100
}
run();
- 20. 引用函式
var a = 100;
function todo() {
console.log(b);
}
function run() {
var b = 200;
todo();
console.log(a);
}
run();
- 21. 引用函式
var a = 100;
function todo() {
console.log(b);
}
function run() {
var b = 200;
todo();
console.log(a); //100
}
run();
- 22. 引用函式
var a = 100;
function todo() {
console.log(b); //undefined
}
function run() {
var b = 200;
todo();
console.log(a); //100
}
run();