完成登录功能,用session记住用户名

登录功能完成:

  1. js:设置return
  2. html:设置
    1. form
    2. input
    3. onclick="return fnLogin()"
  3. py:
    1. @app.route设置methods
    2. GET
    3. POST
      1. 读取表单数据
      2. 查询数据库
        1. 用户名密码对:
          1. 记住用户名
          2. 跳转到首页
        2. 用户名密码不对:
          1. 提示相应错误。

session:

  1. 从`flask`中导入`session`
  2. 设置`SECRET_KEY`
  3. 操作字典一样操作`session`:增加用户名`session['username']=`username
    from flask import Flask,render_template,request,redirect,url_for,session
    from flask_sqlalchemy import SQLAlchemy
    import config
    
    app = Flask(__name__)
    app.config.from_object("config")
    db=SQLAlchemy(app)
    
    class User(db.Model):
        __tablename__ = "user"
        id = db.Column(db.Integer,primary_key=True,autoincrement=True)
        username = db.Column(db.String(20),nullable=False)
        password = db.Column(db.String(20),nullable=False)
        nickname = db.Column(db.String(20))
    #db.create_all()
    
    @app.route('/')
    def vi():
        return render_template("base.html")
    @app.route('/first')
    def base():
        return render_template("base.html")
    
    @app.route("/login",methods=["GET","POST"])
    def login():
        if request.method == "GET":
          return render_template("login.html")
        else:
            usern = request.form.get("usern")
            passw = request.form.get("userp")
            user = User.query.filter(User.username==usern).first()
            if user:
                if user.password == passw:
                    session["user"] = usern
                    # session.permanent = True
                    return redirect(url_for("base"))
                else:
                    return "密码错误,请重新输入!"
            else:
                return "用户名不存在!"
    
    
    @app.route("/regist",methods=["GET","POST"])
    def regist():
        if request.method == "GET":
            return render_template("regist.html")
        else:
            usern1 = request.form.get("newn")
            passw1 = request.form.get("newp")
            user = User.query.filter(User.username==usern1).first()
            if user:
                return "用户名已存在!"
            else:
                user = User(username = usern1,password = passw1)
                db.session.add(user)
                db.session.commit()
                return redirect(url_for("login"))
    
    
    if __name__ == '__main__':
        app.run(debug=True)
    import os
    SQLALCHEMY_DATABASE_URI = 'mysql+pymysql://root:@127.0.0.1:3306/mis_db?charset=utf8'
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    
    SECRET_KEY = os.urandom(24)
    {% extends 'base.html' %}
    {% block title %}
    登录
    {% endblock %}
    {% block head %}
        <link href="{{ url_for("static",filename="css/vv.css") }}" rel="stylesheet" type="text/css">
        <script src="{{ url_for("static",filename="js/login.js") }}"></script>
    {% endblock %}
    {% block main %}
    <body bgcolor="#778899" class="div4">
    <div class="div1">
        <h2 class="title"></h2>
        <form action="{{ url_for("login") }}"method="post">
            <div class="normal-title">
                <a class="div2" href="login.html">登录</a>
                <b>|</b>
                <a  class="div2" href="regist.html">注册</a>
            </div>
    
        <div class="div3">
            用户:<input id="username" type="text" placeholder="请输入昵称" name="usern">
        </div>
        <div class="div3">
            密码:<input id="userpass" type="text" placeholder="请输入密码" name="userp">
        </div>
        <div id="error_box"><br></div>
         <div class="div3">
            <button onclick="return myLogin()">Login</button>
        </div>
        <div class="div2">ByYin</div>
        </form>
    </div>
    <br>
    </body>
    {% endblock %}
    </html>
     function myLogin() {
         var uName = document.getElementById("username");
         var uError = document.getElementById("error_box");
         var uPass =document.getElementById("userpass");
         var isError = true;
         uError.innerHTML="<br>";
         if (uName.value.length < 6||uName.value.length > 20) {
             uError.innerHTML = "用户名为6位到20位!";
             isError = false;
             return isError;
         }
         else if ((uName.value.charCodeAt(0)) >= 48 && uName.value.charCodeAt(0) <= 57) {
             uError.innerHTML = "用户名首字母不能为数字";
             isError = false;
             return isError;
         }
         else for(var i=0;i<uName.value.length;i++){
             if((uName.value.charCodeAt(i)<48||uName.value.charCodeAt(i)>57)&&(uName.value.charCodeAt(i)<97||uName.value.charCodeAt(i)>122)){
                 uError.innerHTML="用户名只能为字母或数字";
                 isError = false;
                 return isError;
             }
         }
         if (uPass.value.length<6||uPass.value.length>20){
             uError.innerHTML="密码为6-20位!";
             isError = false;
             return isError;
         }
         return isError;
     }

     

posted @ 2017-11-22 16:00  100彭楚殷  阅读(105)  评论(0编辑  收藏  举报