文章目录
js的相关操作
1.打印1-100的求和 与平均值
<script>
var x = 100;
var sum=0;
for (var i = 0; i <= x; i++) {
sum=sum+i
console.log(sum);
if(i==100){
pjz=sum/i
console.log( "平均值", pjz)
}
}
</script>
2.打印1-100的偶数和
<script>
var x = 100;
var sum=0;
for (var i = 0; i <= x; i++) {
if(i%2==0){
sum=i+sum
console.log(sum)
}
}
</script>
3.打印1-100的奇数和
<script>
var x = 100;
var sum=0;
for (var i = 0; i <= x; i++) {
if(i%2!=0){
sum=i+sum
console.log(sum)
}
}
</script>
4.100以内7的倍数的和
<script>
var x = 100;
var sum=0;
var qi=0;
for (var i = 0; i <= x; i++) {
if(i%7==0){
sum=sum+i
console.log(sum)
}
}
</script>
5.打印一个矩形
for (var i = 0; i <= 3; i++) {
for (var j = 0; j <= 4; j++) {
document.write("☆");
}
document.write("<br />")
};
打印结果:
5.打印一个正方形
<script>
num=4
for (i = 0; i < num; i++) {
for (j = 0; j < num; j++) {
document.write("☆ ");
}
document.write("<br/>");
}
</script>
打印结果:
6.打印直角三角形
<script>
// i代表个数 j代表行数 记得换行
for (var i = 1; i <= 5; i++) {
for (var j = 1; j <= i; j++) {
document.write("☆")
}
document.write("<br />");
}
</script>
打印结果:
7.打印倒直角三角形
<script>
for (var i = 5; i >= 1; i--) {
for (var j = 0; j < i; j++) {
document.write('☆ ');
}
document.write('<br>');
}
</script>
打印结果:
8.打印等腰三角形
<script>
for (var i = 1; i <= 5; i++) {
for (var j = 0; j < 5 - i; j++) {
document.write('    ');
}
for (var j = 0; j < i; j++) {
document.write('☆      ');
}
document.write('<br>');
}
</script>
9.打印倒等腰直角三角形
<script>
for (var i = 5; i >= 1; i--) {
for (var j= 0; j< 10 - i; j++) {
document.write('  ');
}
for (var j = 0; j < i; j++) {
document.write('☆  ');
}
document.write('<br>');
}
</script>
打印结果:
10.打印九九乘法表
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
*{
margin: 0;
padding: 0;
}
span{
display: inline-block;
border: 1px solid blue;
background-color: deeppink;
text-align: center;
}
span:hover{
background-color: gold;
}
</style>
</head>
<body>
<script>
for (var i = 1; i <= 9; i++) {
for (var j = 1; j <= i; j++) {
document.write("<span>"+" "+j +" "+ " "+"*" +" " +i + "=" + " "+i * j+" "+"</span>");
}
document.write("<br/>")
}
document.write("<br/>")
</script>
</body>
</html>
打印结果:
11.js简易ATM机
<script>
var money = 100;
do {
var i = prompt("这位官人!请输入您要的操作:" + "\n1存钱" + "\n2取钱" + '\n3显示余额' + '\n4退出')
if (i == 1) {
var a = prompt("请输入需要存的钱数")
money += parseInt(a)
alert("您的余额" + money)
} else if (i == 2) {
var b = prompt("请问你需要取多少钱");
money = money - parseInt(b)
if (parseInt(b) > money) {
alert("余额不足")
continue;
}
alert("你的余额" + money)
} else if (i == 3) {
var c = alert('余额' + money);
} else if (i == 4) {
alert("退出");
break;
} else{
alert("输入有误,请重新操作")
}
} while (i != 4);
</script>