完成登录功能，用session记住用户名

Posted 2020-10-15 王卡

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登录功能完成：

js:设置return
html:设置
1. form
2. input
3. ```
onclick="return fnLogin()"
```
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：

从`flask`中导入`session`
设置`SECRET_KEY`

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 import Flask
from flask_sqlalchemy import SQLAlchemy
import config

app = Flask(__name__)
#app.config[\'SECRET_KEY\'] = \'1234567\'
app.config.from_object(config)
db = SQLAlchemy(app)

class User(db.Model):
    __tablename__ = \'user_test\'
    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))
    tel = db.Column(db.String(20))

#db.create_all()

#2.在表中插入一条记录
#user = User(username = \'mis1\',password = \'124\', nickname=\'wk\')
#db.session.add(user)
#db.session.commit()


#3.去表中查询用户名对应的密码和接下来用户输入的密码是否相匹配
#user = User.query.filter(User.username == \'mis1234\').first()
#print(user)
#print(user.id,user.username)#输出查找到的用户名的id,密码等.

#修改查询到的用户名的密码等
#user = User.query.filter(User.username == \'mis1234\').first()
#user.password = \'123\'
#db.session.commit()

#再次插入一条记录
#user = User(username = \'wkkkkkk\',password = \'123456\', nickname=\'kk\')
#db.session.add(user)
#db.session.commit()

#删除一条记录
#user = User.query.filter(User.username == \'mis1234\').first()
#db.session.delete(user)
#db.session.commit()




@app.route(\'/\')
def index():
    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(\'uname\')
        passw = request.form.get(\'upass\')
        user = User.query.filter(User.username==usern).first()
        if user:
            if user.password == passw:
                session[\'user\'] = usern;
                return redirect(url_for(\'index\'))
            else:
                return \'password error!\'
        else:
            return \'username is not exister!\'



@app.route(\'/register/\',methods=[\'GET\',\'POST\'])
def register():
    if request.method ==\'GET\':
        return  render_template(\'register.html\')
    else:
        usern = request.form.get(\'uname\')
        teln = request.form.get(\'number\')
        passw = request.form.get(\'upass\')
        user = User.query.filter(User.username==usern).first()
        if user:
            return \'username existed\'
        else:
            user1= User(username=usern,tel=teln,password=passw)
            db.session.add(user1)
            db.session.commit()
            return redirect(url_for(\'login\'))


@app.route(\'/question/\',methods=[\'GET\',\'POST\'])
def question():
    return render_template(\'question.html\')

if __name__ == \'__main__\':
    app.run(debug=True)

function fnLogin(){
    var oUname = document.getElementById("uname");
    var oUpass = document.getElementById("upass");
    var oError = document.getElementById("error_box");
    var isError = true;
    oError.innerHTML="<br>";
    //uname
    if (oUname.value.length>10 || oUname.value.length < 6){

        oError.innerHTML="用户名必须是6-10位！";
        isError = false;
        return isError;
    }else if((oUname.value.charCodeAt(0)>=48)&& (oUname.value.charCodeAt(0))<=57){
        oError.innerHTML="用户名首字母不能是数字！";
        isError = false;
        return isError;
    }else for(var i=0;i<oUname.value.length;i++){
        if((oUname.value.charCodeAt(i)<48 || oUname.value.charCodeAt(i)>57) && (oUname.value.charCodeAt(i)<97 || oUname.value.charCodeAt(i)>122)){
            oError.innerHTML="用户名只能为数字和字母";
            isError = false;
            return isError;
        }


    }
    //upass
    if(oUpass.value.length>10 || oUpass.value.length<6 ){
        oError.innerHTML="用户密码6-10位！";
        isError = false;
        return isError;
    }
    //window.alert("登录成功！")
    return isError;
}

#SQLALCHEMY_DATABASE_URI = \'mysql+pymysql://root:wk21640913@127.0.0.1:3306/mis_1test?charset=utf8\'
import  os
SQLALCHEMY_DATABASE_URI = \'mysql+pymysql://root:@127.0.0.1:3306/mis_1?charset=utf8\'
SQLALCHEMY_TRACK_MODIFICATIONS = False
SECRET_KEY = os.urandom(24)

{% extends \'base.html\' %}
    {% block title %}
        登录
    {% endblock %}
{% block head %}
    <!--<title>login</title>-->
    <!--<link href="../static/css/login.css" rel="stylesheet" type="text/css">
    <script src="../static/js/login.js"></script>-->
     <link rel="stylesheet" type="text/css" href="{{ url_for(\'static\',filename=\'css/login.css\')}}">
    <script src="{{ url_for(\'static\',filename=\'js/login.js\') }}" type="text/javascript"></script>


{%  endblock %}

{% block main %}
      <div class="box">
          <h2>登录</h2>
          <form method="post" action="{{ url_for(\'login\') }}">
          <div class="input_box">
              username:<input id="uname" type="text" placeholder="请输入用户名" name="uname">
          </div>
          <div class="input_box">
              password:<input id="upass" type="password" placeholder="请输入密码"  name="upass">
          </div>
          <div id="error_box" ><br></div>
          <div class="input_box">
              <button id="button" onclick=" return fnLogin()">登录</button>&nbsp&nbsp&nbsp&nbsp&nbsp
              <button id="button" onclick="window.location.replace({{ url_for("register") }})">注册</button>
          </div>
      </form>
      </div>
{% endblock %}

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