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

        存到数据库中

        redirect重定向到登录页

js：

function fnRefist() {
    var oUname = document.getElementById("uname")
    var oError = document.getElementById("error_box")
    var oUpass = document.getElementById("upass")
    var oUpass1 = document.getElementById("upass1")

    oError.innerHTML = "<br>"
    if (oUname.value.length < 6 || oUname.value.length > 20) {
        oError.innerHTML = "用户名必须在6-20之间";
        return;
    } else if ((oUname.value.charCodeAt(0) >= 48) && (oUname.value.charCodeAt(0) <= 57)) {
        oError.innerHTML = "首字母不能为数字";
        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 = "只能填写数字或字母";
            return;
        }
    }
    // oUpass
    if (oUpass.value.length > 20 || oUpass.value.length < 6) {
        oError.innerHTML = "密码必须在6-20之间";
        return;
    } else if (oUpass.value!= oUpass1.value) {
        document.getElementById("error_box").innerHTML = "两次密码不一致"
        return false;
    }
    return true;
    window.alert("注册成功！")

HTML：

{% extends'index.html' %}

{% block title %}注册 {% endblock %}

{% block head %}
    <link rel="stylesheet" type="text/css" href="{{ url_for('static',filename='css/886.css') }}">
    <script src="{{ url_for('static',filename='js/00.js')}}"></script>
{% endblock %}

{% block main %}
    <div class="box">
        <h2 class="dd">注册</h2>
        <form action="{{ url_for('regist') }}"method="post">
        <div class="input_box">
            <input id="uname" type="text" placeholder="请输入用户名" name="username">
            <br><input id="unickname" type="text" placeholder="请输入昵称" name="nickname">
        </div>
        <div class="input_box">
            <br><input id="upass" type="password" placeholder="请输入密码" name="password">
            <br><input id="upass1" type="password" placeholder="请确认密码">
    </div>
            <br><div id="error_box"><br></div><br>
        <div>
            <br>
            <br><button class="jj" onclick="fnRefist()">注册</button>
        </div>
        </form>
    </div>
{% endblock %}

主py：

from flask import Flask,render_template,request,redirect,url_for,session
from flask_sqlalchemy import SQLAlchemy
import config
from functools import wraps
from datetime import datetime


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
# user = User(username='mis1114',password = 'mis1114',nickname='mis1114')
# db.session.add(user)
# db.session.commit()
# # 查询
# User.query.filter(User.username == 'mis1114').first()
# #修改
# user =User.query.filter(User.username =='mis1114').first()
# user.password='23456'
# print(user.username,user.password)
# db.session.commit()
# # 删除
# user =User.query.filter(User.username =='mis1114').first()
# db.session.delete(user)
# db.session.commit()


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

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

@app.route('/regist/',methods=['GET','POST'])
def regist():
    if request.method=='GET':
         return render_template('regist.html')
    else:
        username=request.form.get('username')
        password=request.form.get('password')
        nickname = request.form.get(' nickname')
        user = User.query.filter(User.username==username).first()
        if user:
            return u'username existed'
        else:
            user = User(username=username, password= password, nickname=nickname)
            db.session.add(user)
            db.session.commit()
            return redirect(url_for('login'))

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

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