- js的系统性学习
- js案例
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <script> var year = prompt('请输入您的出生年份') var str = 2021 - year //year取过来是 字符串类型 但这里用的减法 有隐式转化 alert('您今年已经'+ str + '岁了') </script> </head> <body> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <script> var fruit = prompt('请输入查询的水果:') switch (fruit) { case '苹果': alert('3.5元/斤') break; case '榴莲': alert('26.5元/斤') break; case '葡萄': alert('10.5元/斤') break; default : alert('没有该水果') } </script> </head> <body> </body> </html>
