Flask源码示例-1

深碍√TFBOYSˉ_ 2022-10-16 12:26 158阅读 0赞

## Flask源码示例-1 ##

首先看一下文件架构：templates中放入html文件  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L015TnVUaA_size_16_color_FFFFFF_t_70_pic_center]

1.先运行起来：s2.py文件查看run()的源码，会调用到run\_simple()

#s1.py
    from werkzeug.wrappers import Request,Response
    from werkzeug.serving import run_simple
    
    
    @Request.application
    def hello(request):
        return Response('Hello world')
    
    if __name__ == '__main__':
        run_simple('localhost',4000,hello)

#s2.py
    from flask import Flask
    
    app = Flask(__name__)
    
    @app.route('/index')
    def index():
        return 'hello world'
    
    if __name__ == '__main__':
        app.run()

最重要的示例：

#app.py
    #from flask import Flask,render_template
    #from flask import Flask,render_template,request  #request用来获取用户提交的数据
    from flask import Flask,render_template,request,redirect,session
    
    #app = Flask(__name__,template_folder='')   template用来指定html文件存放的文件夹
    app = Flask(__name__)
    app.secret_key = 'zzy'    #为了session['user_info'] = user不出错
    app.debug = True          #自动重启
    
    USER_DICT = {
        
        '1':{
        'name':'zzy','age':27},
        '2':{
        'name':'ftg','age':26},
        '3':{
        'name':'no_one','age':17}
    }
    
    @app.route('/index')
    def index():
        #return "欢迎登录"
        user_info = session.get('user_info')
        if not user_info:
            return redirect('/login')
        #return "欢迎登陆"
        return render_template('index.html',user_dict = USER_DICT)
    
    #@app.route('/login')
    @app.route('/login',methods=['GET','POST'])
    def login():
        #print('请求来了')
        #return render_template('login.html')
        if request.method == 'GET':
            return render_template('login.html')
        #request.args   #获取GET传来的值
        #request.form   #获取POST传来的值
        user = request.form.get('user')
        pwd = request.form.get('pwd')
        if user == 'zzy' and pwd == 'zzy' :
            #pass
            #使用重定向
            #return redirect('/index')
            #session['user_info'] = user
            #RuntimeError: The session is unavailable because no secret key was set
            #Set the secret_key on the application to something unique and secret.
            session['user_info'] = user
            return redirect('/index')
        else:
            #return render_template('login.html')
            return render_template('login.html',msg='用户名或密码错误')
            #return render_template('login.html',**{'msg':'用户名或者密码错误'})
    
    @app.route('/logout')
    def logout():
        del session['user_info']
        return redirect('/login')
    
    @app.route('/detail')
    def detail():
        user_info = session.get('user_info')
        if not user_info:
            return redirect('/login')
    
        uid = request.args.get('uid')
        info = USER_DICT.get(uid)
    
        return render_template('detail.html',info = info)
    
    if __name__ == '__main__':
        app.run()

2.对应的html文件：

index.html
    <!DOCTYPE html>
    <html lang="zh-cn">
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width,initial-scale=1">
        <title>Title</title>
    </head>
    <body>
        <ul>
            {% for k,v in user_dict.items() %}
                <li>{
       {v.name}} <a href="/detail?uid={
         {k}}">查看详细</a></li>
            {% endfor %}
        </ul>
    </body>
    </html>

login.html
    <!DOCTYPE html>
    <html lang="zh-cn">
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width,initial-scale=1">
        <title>zzy-系统登录</title>
    </head>
    <body>
        <h1>登录</h1>
        <form method="post">
            <input type="text" name="user">
            <input type="password" name="pwd">
            <input type="submit" value="提交">{
       {msg}}
        </form>
    </body>
    </html>

detail.html
    <!DOCTYPE html>
    <!DOCTYPE html>
    <html lang="zh-cn">
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width,initial-scale=1">
        <title>Title</title>
    </head>
    <body>
        <h1>详细信息</h1>
        <div>{
       {info.name}}</div>
        <div>{
       {info.age}}</div>
    </body>
    </html>

3.运行示例  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L015TnVUaA_size_16_color_FFFFFF_t_70_pic_center 1]

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L015TnVUaA_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221014/113832ec10d6442a837e6b00eb3fdc63.png