基础的JavaScript知识总结(六)函数、初始作用域（下）

//a是全局变量var a = 123;function test(){ console.log(a);//打印出来是123
 //b是局部变量
 var b = 123; function demo(){ var c = 234; console.log(a); console.log(b);
 } console.log(c);//报错c is not defined;};
test();console.log(b);//报错b is not defined
function test(){ var a = 123;
}function demo(){ var b = 12;
}//不能相互访问