function myFunction ()
{
var x = 5;
return x;
}
var myVar = myFunction();
console.log (x); // 5
function myFunction (a,b)
{
if (a>b)
{
return;
}
x=a+b;
console.log (x);
}
this.myFunciton (3,2); // a 大于 b,则上面的代码将退出函数,并不会计算 a 和 b 的总和
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
</head>
<body>
<script>
function myfunction(a,b){
return a*b;
};
const test = this.myfunction(1,2);
console.log(">>",test);
function myFunction(a,b)
{
if (a>b)
{
console.log(a,b);
return; //break 语句可用于跳出循环。break 语句跳出循环后,会继续执行该循环之后的代码(如果有的话):
}
x=a+b;
console.log(">>",x);
};
const t = this.myFunction(3,2);
</script>
</body>
</html>
全局变量
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
</head>
<body>
<script>
var data = 2;
function mytest (){
data = 4;
};
this.mytest();
console.log("data>>",data); //data 4
console.log("window",window.data); //window 4
</script>
</body>
</html>
for 和 break 、continue
function my2() {
var x = '',
i = 0;
for (; i < 4; i++) {
if (i == 3) {
break;
}
x = x + i;
console.log(x); // 0 01 012
}
console.log('>>', x); // >> 012
}
this.my2();
function my3() {
for (var i = 0;i < 4; i++) {
console.log(i); //0 //1 //2 //3
}
console.log(i); //4
}
this.my3();
function my4(){
var x="",i=0;
for (i=0;i<10;i++){
if (i==3){
continue;
}
x=x + i;
}
console.log(x); // 012456789
}