完成注册功能

js文件： onclick函数return True时才提交表单，return False时不提交表单。
html文件：
1. <form>中设置 action和method="post"
2. <input> 中设置 name
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

py:

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)


db.create_all()
@app.route('/')
def daohang():
    return render_template('daohang.html')
@app.route('/login/',methods=['GET','POST'])
def login():
    return render_template('1031.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 'username existed'
        else:
            user=User(username=username,password=password)
            db.session.add(user)
            db.session.commit()
            return redirect(url_for('login'))


@app.route('/biaoqian/')
def biaoqian():
    return render_template('biaoqian.html')
if __name__ == '__main__':
    app.run(debug=True)

regist.html:

{% extends'daohang.html' %}
{% block title %}注册{% endblock %}
{% block head %}
    <link rel="stylesheet" type="text/css" href="{{ url_for('static',filename='css/1031.css') }}">
    <script src="{{ url_for('static',filename='js/zhuce1.js') }}"></script>
{% endblock %}

{% block main %}
<div class="box" >
    <h2>注册</h2>
    <form action="{{ url_for('regist') }}"method="post">
    <div class="input_box">
        <input id="uname" type="text" placeholder="设置用户名" name="username">
    </div>
    <div class="input_box">
        <input id="upass" type="password" placeholder="设置密码" name="password">
    </div>
    <div class="input_box">
        <input id="upass1" type="password" placeholder="请再次输入密码">
    </div>
    <div id="error_box"><br></div>
    <div class="input_box">
        <button onclick="fnLogin()">注册</button>
    </div>
        </form>
</div>
{% endblock %}

{% extends'daohang.html' %}
{% block title %}登录{% endblock %}
{% block head %}
    <link rel="stylesheet" href="{{ url_for('static',filename='css/1031.css') }}" type="text/css">
    <script src="{{ url_for('static',filename='/js/js.js') }}"></script>'

{% endblock %}
{% block main %}
    <div class="box" >
    <h2>登录</h2>
        <form action="{{ url_for('login') }}"method="post">
    <div class="input_box">
        <input id="uname" type="text" placeholder="请输入用户名" name="username">
    </div>
    <div class="input_box">
        <input id="upass" type="password" placeholder="请输入密码" name="password">
    </div>
    <div id="error_box"><br></div>
    <div class="input_box">
        <button onclick="fnLogin()">登录</button>
        <button type="button" onclick=window.alert("账号密码为空，请输入！")>未输入账号密码</button>
    </div>
        </form>>
</div>
{% endblock %}

regist.js:

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


    oError.innerHTML = "<br>"
    // uname
    if (oUname.value.length > 20 || oUname.value.length < 6) {
        oError.innerHTML = "用户名6—20位";
        return;
    } else if (oUname.value.charCodeAt((0) >= 48) && (oUname.value.charCodeAt(0) <= 57)) {
        oError.innerHTML = "首字母不能是数字";
        return
    } else for (var i = 0; i < oUname.value.length; i++) {
        if ((oUname.value.charCodeAt(i) < 48) || (oUname.value.charCodeAt(0) > 57) && (oUname.value.charCodeAt(i) < 97) || (oUname.value.charCodeAt(0) > 122)) {
            oError.innerHTML = "只能是字母或数字";
            return;
        }
    }
    // upass
    if (oUpass.value.length > 20 || oUpass.value.length < 6) {
        oError.innerHTML = "密码6—20位";
        return;
    } else if (oUpass.value != oUpass1.value) {
        oError.innerHTML = "两次密码不一致";
        return false;
    }
    return true;
    window(alert("注册成功！"))
}