変数値の種類:数値タイプと参照タイプ
1121 ワード
javascript高級プログラム設計70
var a=10sayHi();function sayHi(){
// : 、 , 69
var color = "red";
function changeColor(color){ // color changeColor 。
console.log(arguments) //[callee:function,Symbol()]
if(color === "red"){
color = "blue";
}else{
color = "blue";
}
}
changeColor(color);
console.log(color) //red
var color = "red";
function changeColor(){
console.log(arguments) //[callee:function,Symbol()]
if(color === "red"){
color = "blue";
}else{
color = "blue";
}
}
changeColor();
console.log(color) //blue
//グローバル変数と局所変数var a=10;sayHi();function sayHi(){var a = a + 10;
alert(a);
return a; //return a a, alert(a) //10
}alert(a)alert(sayHi()+10)実行結果:NaN 10 NaN NaNvar a=10sayHi();function sayHi(){
var a = "a" + 10;
alert(a);
alert(typeof a);
return a; //return a a, alert(a) //10
}alert(a)alert(sayHi()+10)実行結果:a 10 string 10 a 10 string a 1010