wtforms组件使用

pip install wtforms

from wtforms.fields import simple
from wtforms.fields import core
from wtforms.fields import html5

from wtforms import validators  # 校验规则
from wtforms import widgets  # 输入框类别：下拉框、输入框、长文本等等

from wtforms import Form
from wtforms.fields import simple
from wtforms import validators


class RegFrom(Form):
    name = simple.StringField(label="用户名",
                              validators=[validators.DataRequired(message="用户名不能为空"),
                                          validators.Length(min=2, max=8, message="用户名最小两位，最大8位")])
    pwd = simple.PasswordField(label="密码",
                               validators=[validators.DataRequired(message="密码不能为空"),
                                           validators.Regexp(regex="^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$@$!%*?&])[A-Za-z\d$@$!%*?&]{8,}",
                                                             message=‘密码至少8个字符，至少1个大写字母，1个小写字母，1个数字和1个特殊字符‘)])
    # pwd = simple.PasswordField(label="密码", validators=[validators.DataRequired(message="密码不能为空"), ])
    rep_pwd = simple.PasswordField(label="再次输入密码",
                                   validators=[validators.DataRequired(message="重复密码不能为空"),
                                               validators.EqualTo("pwd", message="两次密码不一致")])

from flask import Flask, render_template, current_app
from flask import Blueprint
from flask import request
from flask import session
from flask_wtforms.forms import register_froms

reg = Blueprint(‘reg‘, __name__)


@reg.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "GET":
        forms = register_froms.RegFrom()  # 注册form表单
        return render_template("register.html", forms=forms)
    forms = register_froms.RegFrom(formdata=request.form)  # 将post数据传入
    if forms.validate():  # 校验post请求数据
        return "ok"
    return render_template("register.html", forms=forms)

<!DOCTYPE html>
<html lang="zn-CH">
<head>
    <meta charset="UTF-8">
    <title>注册</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<div>
    <form action="" method="post" novalidate>
        <div>
            {% for from in forms %}
                <p>{{ from.label }}: {{ from }} {{ from.errors[0] }}</p>
            {% endfor %}
            <input type="submit">
        </div>
    </form>
</div>
</body>
</html>

from wtforms import Form
from wtforms.fields import simple
from wtforms.fields import core
from wtforms.fields import html5
from wtforms import validators
from wtforms import widgets
import helper
class UserForm(Form):
    city = core.SelectField(
        label=‘城市‘,
        choices=(),  # 在__init__中从数据库中获取
        coerce=int
    )
    name = simple.StringField(label=‘姓名‘)

    def __init__(self,*args,**kwargs):
        super(UserForm,self).__init__(*args,**kwargs)

        self.city.choices=helper.fetch_all(‘select id,name from tb1‘,[],type=None)

import pymysql
from DBUtils.PooledDB import PooledDB, SharedDBConnection
import pymysql

POOL = PooledDB(
        creator=pymysql,  # 使用链接数据库的模块
        maxconnections=6,  # 连接池允许的最大连接数，0和None表示不限制连接数
        mincached=2,  # 初始化时，链接池中至少创建的空闲的链接，0表示不创建
        maxcached=5,  # 链接池中最多闲置的链接，0和None不限制
        maxshared=3,
        # 链接池中最多共享的链接数量，0和None表示全部共享。PS: 无用，因为pymysql和MySQLdb等模块的 threadsafety都为1，所有值无论设置为多少，_maxcached永远为0，所以永远是所有链接都共享。
        blocking=True,  # 连接池中如果没有可用连接后，是否阻塞等待。True，等待；False，不等待然后报错
        maxusage=None,  # 一个链接最多被重复使用的次数，None表示无限制
        setsession=[],  # 开始会话前执行的命令列表。如：["set datestyle to ...", "set time zone ..."]
        ping=0,
        # ping MySQL服务端，检查是否服务可用。# 如：0 = None = never, 1 = default = whenever it is requested, 2 = when a cursor is created, 4 = when a query is executed, 7 = always
        host=‘127.0.0.1‘,
        port=3306,
        user=‘root‘,
        password=‘123456‘,
        database=‘s9day119‘,
        charset=‘utf8‘
    )

def connect(type):
    conn = POOL.connection()
    cursor = conn.cursor(cursor=type)
    return conn,cursor


def connect_close(conn,cursor):
    cursor.close()
    conn.close()

def fetch_all(sql,args,type=pymysql.cursors.DictCursor):   # type=pymysql.cursors.DictCursor返回的数据为字典，传入None时，返回元祖
    conn,cursor = connect(type)

    cursor.execute(sql, args)
    record_list = cursor.fetchall()
    connect_close(conn,cursor)

    return record_list


def fetch_one(sql, args):
    conn, cursor = connect()
    cursor.execute(sql, args)
    result = cursor.fetchone()
    connect_close(conn, cursor)

    return result


def insert(sql, args):
    conn, cursor = connect()
    row = cursor.execute(sql, args)
    conn.commit()
    connect_close(conn, cursor)
    return row