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 Login(){
            var un=document.getElementById("id");
            var us=document.getElementById("password");
            var er=document.getElementById("error_box");
            er.innerHTML = "<br>";
            if(un.value.length<6||un.value.length>20){
            er.innerHTML="用户名必须在6-20个字符之间";
            return;
            }else if((un.value.charCodeAt(0))>=48 && un.value.charCodeAt(0)<=57){
                er.innerHTML = "首字母不能为数字"
                return;
            }else for(var i=0;i<un.value.length;i++){
                if((un.value.charCodeAt(i)<48)||(un.value.charCodeAt(i)>57)&&(un.value.charCodeAt(i)<97)&&(un.value.charCodeAt(i)>122)){
                    er.innerHTML="用户名只能为数字和字母"
                    return;
                }
            }
            if(us.value.length<6||us.value.length>20){
            er.innerHTML="密码必须在6-20个字符之间";
            return;
            }
            window.alert("登陆成功！")
        }
　　　　function Zhuce() {
        var un=document.getElementById("zcid");
        var us=document.getElementById("zcpassword");
        var rpa=document.getElementById("repassword");
        var er=document.getElementById("error_box1");
            er.innerHTML = "<br>";
            if(un.value.length<6||un.value.length>20){
            er.innerHTML="用户名必须在6-20个字符之间";
            return;
            }else if((un.value.charCodeAt(0))>=48 && un.value.charCodeAt(0)<=57){
                er.innerHTML = "首字母不能为数字"
                return;
            }else for(var i=0;i<un.value.length;i++){
                if((un.value.charCodeAt(i)<48)||(un.value.charCodeAt(i)>57)&&(un.value.charCodeAt(i)<97)&&(un.value.charCodeAt(i)>122)){
                    er.innerHTML="用户名只能为数字和字母"
                    return;
                }
            }
            if(us.value.length<6||us.value.length>20){
                 er.innerHTML="密码必须在6-20个字符之间";
                 return;
            }else for(var i=0;i<us.value.length;i++){
                if(us.value.charCodeAt(i)!=rpa.value.charCodeAt(i)){
                    er.innerHTML="密码不一致"
                }
            }
    }

HTML:

<div class="center-block" id="zhucebox">
    <div class="panel panel-primary" id="zhucebox1_1">
        <div class="panel-heading">
            <h2 class="panel-title">注册</h2>
        </div>
        <br>
        <form class="bs-example bs-example-form" role="form" action="{{ url_for('register') }}" method="post">
            <div class="input-group">
                <span class="input-group-addon"></span>
                <input type="text" class="form-control" id="zcid" placeholder="请输入用户名" name="zcid">
            </div>
            <br>
            <div class="input-group">
                <span class="input-group-addon"></span>
                <input type="password" class="form-control" id="zcpassword" placeholder="请设置密码" name="zcpassword">
            </div>
            <br>
            <div class="input-group">
                <span class="input-group-addon"></span>
                <input type="password" class="form-control" id="repassword" placeholder="请再次输入密码">
            </div>
            <div id="error_box1">
                <br>
            </div>
            <br>
            <label><input type="submit" class="btn btn-default" value="注册" onclick="Zhuce()"></input></label>
        </form>
    </div>
</div>

主py文件：

from flask import Flask, render_template, request, url_for, sessions, redirect
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)

#创建表格
# db.create_all()

#数据添加方法
# user=User(username='mis777789',password='g6666')
# db.session.add(user)
# db.session.commit()

# 数据的修改方法
# user = User.query.filter(User.username=='mis777789').first
# user.password='0.0.0.0'
# db.session.commit()

# 数据的删除方法
# user = User.query.filter(User.username=='mis777789').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('/regis',methods=['GET','POST'])
def register():
    if request.method=='GET':
        print('1')
        return render_template('Zhuce.html')
    else:
        print('2')
        username=request.form.get('zcid')#与html页面名字相同
        password=request.form.get('zcpassword')
        user=User.query.filter(User.username==username).first()
        if user:
            return 'exit'
        else:
            user=User(username=username,password=password)
            db.session.add(user)
            db.session.commit()
            return redirect(url_for('login'))



@app.route('/fankui')
def fankui():
    return render_template("page_fankui.html")

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