完成注册功能

1. js文件： onclick函数return True时才提交表单，return False时不提交表单。
2. html文件：
   1. <form>中设置 action和method="post"
   2. <input> 中设置 name
3. 主py文件中：
   1. from flask import  request, redirect, url_for
   2. @app.route('/regist/', methods=['GET', 'POST’])

def regist():

   if request.method == 'GET':

        return render_template('regist.html')

   else:

        username = request.form.get(‘username’)#获取form中的数据

        判断用户名是否存在:存在报错

  不存在，存到数据库中

       redirect重定向到登录页

py文件：

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(50))


#db.create_all()

#增加数据
user=User(username = 'mis1234',password = '111111')
db.session.add(user)
db.session.commit()

#查询数据
user=User.query.filter(user.username == 'mis1234').first()
print(user.id,user.username,user.password)


#修改数据
user=User.query.filter(user.username == 'mis3333').first()
user.password = '0000'
db.session.commit()

#删除数据
user=User.query.filter(user.username == 'mis3333').first()
db.session.delete(user)
db.session.commit()

@app.route('/')
def base():
    return render_template('base.html')


@app.route('/login/')
def login():
    return render_template('login.html')

@app.route('/zhuche/', methods=['GET','POST'])
def login ():
    if request.method =='GET':
        return render_template('zhuce.html')#跳转注册
    else:
        usern = request.form.get('username')
        passw = request.form.get('password')
        nickn = request.form.get('nickname')
        user = User.query.filter(User.username == usern).first()
        if user:
            return u'username existed'
        else:
            user1 = User(username = usern,password = passw,nickname=nickn)
            db.session.add(user1)#数据库操作
            db.session.commit()
            return redirect(url_for('gg'))

@app.route('/question/')
def question():
    return render_template('question.html')

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

function fnRegister() {
    var oUname = document.getElementById("uname");
    var oError = document.getElementById("error_box");
    var oUiphone = document.getElementById("uiphone");
    var oUpass = document.getElementById("upass");
    var oUpass1 = document.getElementById("upass1");
     var oUpass = document.getElementById("upass").value;
     var oUpass1 = document.getElementById("upass1").value;
    if (oUpass1!=oUpass){
    document.getElementById("error_box"),innerHTML="两次密码不一致";
    return false;}
   return true;
    oError.innerHTML = "<br>"

    if (oUname.value.length < 6 || oUname.value.length > 12) {
        oError.innerHTML = "用户名6-12";
        return;
    } else if ((oUname.value.charCodeAt(0) >= 48) && (oUname.value.charCodeAt(0) <= 57)) {
        oError.innerHTML = "第一位只能是字母";
        return;
    } 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 = "只能是字母或数字";
            return;
        }
    }
    if (oUpass.value.length < 6 || oUpass.value.length > 12) {
        oError.innerHTML = "密码6-12位";
        return;
    }
    if (oUpass1.value != oUpass.value) {
        oError.innerHTML = "rewrite your PIN";
        return;
    }
    if (oUpass!= oUpass1) {
         document.getElementById("error_box").innerHTML = "两次密码不一样";
       return;
   }
   window.alert("注册成功")
}

HTML文件：

{% extends 'base.html' %}
{% block zhucetitle %}注册{% endblock %}
{% block zhucehead %}
    <title>Registration</title>
    <link rel="stylesheet" type="text/css" href="../static/css/zhuce.css">
    <script src="../static/js/zhuce.js"></script>
{% endblock %}
{% block zhucebody %}
     <div class="box">
          <h2>注册</h2>

     <form action="{{ url_for('login') }}" method="post">
          <div class="input_box">
                <input type="text" id="user" placeholder="请输入用户名" name="username">
          </div>


          <div class="input_box">
                <input type="password" id="upass" placeholder="请输入密码"name="password">
          </div>

          <div class="input_box">
                <input type="password" id="upass1" placeholder="请再次确认密码">
          </div>

          <div id="error_box"><br>
          </div>

          <div class="input_box">
            <button onclick="fnRegistration()">Enter</button>
          </div>
         </form>
     </div>
{% endblock %}