5，做一个用户登录之后查看学员信息的小例子

需求:

1. 用户名: oldboy 密码: oldboy123

2. 用户登录成功之后跳转到列表页面

3. 失败有消息提示,重新登录

4.点击学生名称之后,可以看到学生的详细信息

后端:

 1 from flask import Flask
 2 from flask import request
 3 from flask import render_template
 4 from flask import redirect
 5 
 6 USER = {'username': 'oldboy', 'password': "oldboy123"}
 7 
 8 STUDENT_DICT = {
 9     1: {'name': 'Old', 'age': 38, 'gender': '中'},
10     2: {'name': 'Boy', 'age': 73, 'gender': '男'},
11     3: {'name': 'EDU', 'age': 84, 'gender': '女'},
12 }
13 
14 app = Flask(__name__)
15 
16 
17 @app.route("/login", methods=["GET", "POST"])
18 def login():
19     if request.method == "POST":
20         if request.form["username"] == USER["username"] and request.form["password"] == USER["password"]:
21             return redirect("/student_list")
22         return render_template("login.html", msg="用户名密码错误")
23 
24     return render_template("login.html", msg=None)  # 如果前端Jinja2模板中使用了msg,这里就算是传递None也要出现msg
25 
26 
27 @app.route("/student_list")
28 def student():
29     return render_template("student_list.html", student=STUDENT_DICT)
30 
31 
32 @app.route("/info")
33 def student_info():
34     stu_id = int(request.args["id"])
35     stu_info = STUDENT_DICT[stu_id]
36     return render_template("student.html", student=stu_info, stu_id=stu_id)
37 
38 
39 app.run("0.0.0.0", 5000, debug=True)

相信写的代码才是最好的

前端:

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Welcome to Old Boy EDU</title>
 6 </head>
 7 <body>
 8     <form method="post">
 9         用户名:<input type="text" name="username">
10         密码:<input type="text" name="password">
11         <input type="submit" value="登录">
12         {{ msg }}
13     </form>
14 </body>
15 </html>

登录页面前端代码

student_list.html:

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Old Boy EDU</title>
 6 </head>
 7 <body>
 8 Welcome to Old Boy EDU
 9 <table border="2xp">
10     <thead>
11         <tr>
12             <td>id</td>
13             <td>name</td>
14             <td>option</td>
15         </tr>
16     </thead>
17     <tbody>
18         {% for foo in student %}
19             <tr>
20                 <td>{{ foo }}</td>
21                 <td>{{ student[foo].name }}</td>
22                 <td><a href="/info?id={{ foo }}">详细</a></td>
23             </tr>
24         {% endfor %}
25     </tbody>
26 </table>
27 </body>
28 </html>

一点儿也不难

student.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Old Boy EDU</title>
 6 </head>
 7 <body>
 8 Welcome to Old Boy EDU
 9 <table border="1px">
10     <thead>
11     <tr>
12         <td>id</td>
13         <td>name</td>
14         <td>age</td>
15         <td>gender</td>
16     </tr>
17     </thead>
18     <tbody>
19     <tr>
20         <td>{{ stu_id }}</td>
21         <td>{{ student.name }}</td>
22         <td>{{ student["age"] }}</td>
23         <td>{{ student.get("gender") }}</td>
24     </tr>
25     </tbody>
26 </table>
27 <div><a href="/student_list">返回</a></div>
28 </body>
29 </html>

写不出来说明你没动脑子