wtforms

一、简介

WTForms是一个支持多个web框架的form组件，主要用于对用户请求数据进行验证。

pip3 install wtforms

二、用户登录注册示例

from flask import Flask, request, render_template, redirect
from wtforms import Form
from wtforms import widgets
from wtforms import validators
from wtforms.fields import simple

app = Flask(__name__)


class MyValidators(object):
    """自定义验证规则"""
    def __init__(self,message):
        self.message = message

    def __call__(self, form, field):
        black_list = ["shabi", "傻逼"]
        print("用户输入的信息：", field.data)
        if field.data not in black_list:
            return None
        raise validators.ValidationError(self.message)


class LoginForm(Form):
    username = simple.StringField(
        label="账号",
        validators=[
            MyValidators(message="用户名非法"),  # 自定义验证规则
            validators.DataRequired(message="用户名不能为空"),
            validators.Length(min=2, max=8, message="用户名长度必须大于%(min)d且小于%(max)d")
        ],
        widget=widgets.TextInput(),  # TextInput(input_type="test")
        render_kw={"placeholder": "请输入账号"}
    )
    password = simple.PasswordField(
        label="密码",
        validators=[
            validators.DataRequired(message="密码不能为空"),
            validators.Length(min=6, message="用户名长度必须大于%(min)d"),
            validators.Regexp(regex="d+", message="密码必须是数字")
            # validators.Regexp(regex="^(?=.*[a-z])(?=.*[A-Z])(?=.*d)(?=.*[$@$!%*?&])[A-Za-zd$@$!%*?&]{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")
        ],
        widget=widgets.PasswordInput(),
        render_kw={"placeholder": "请输入密码"}
    )


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "GET":
        form = LoginForm()
        return render_template("login.html", form=form)
    form = LoginForm(formdata=request.form)
    if form.validate():  # 通过验证
        print(form.data)
        return redirect("https://www.cnblogs.com/believepd/")
    else:
        print(form.errors)
        return render_template("login.html", form=form)


if __name__ == "__main__":
    app.run()

app.py

<!DOCTYPE html>
<html lang="zh-cn">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form method="post" novalidate>
    <div>{{ form.username.label }}{{ form.username }}{{ form.username.errors[0] }}</div>
    <div>{{ form.password.label }}{{ form.password }}{{ form.password.errors[0] }}</div>
    <div><input type="submit" value="登录"></div>
</form>
</body>
</html>

注册

from flask import Flask, request, render_template
from wtforms import Form
from wtforms import widgets
from wtforms import validators
from wtforms.fields import core
from wtforms.fields import html5
from wtforms.fields import simple

app = Flask(__name__)


class RegisterForm(Form):
    username = simple.StringField(
        label="账号",
        validators=[
            validators.DataRequired(message="账号不能为空")
        ],
        widget=widgets.TextInput(),
        render_kw={"class": "c1"},
        default="pd"  # 默认值
    )
    password = simple.PasswordField(
        label="密码",
        validators=[
            validators.DataRequired(message="密码不能为空")
        ],
        widget=widgets.PasswordInput(),
        render_kw={"class": "c2"}
    )
    password_confirm = simple.PasswordField(
        label="重复密码",
        validators=[
            validators.DataRequired(message="重复密码不能为空"),
            validators.EqualTo("password", message="两次密码输入不一致")
        ],
        widget=widgets.PasswordInput(),
        render_kw={"class": "c3"}
    )
    email = html5.EmailField(
        label="邮箱",
        validators=[
            validators.DataRequired(message="邮箱不能为空"),
            validators.Email(message="邮箱格式错误")
        ],
        widget=widgets.TextInput(input_type="email"),
        render_kw={"class": "c4"}
    )
    gender = core.RadioField(
        label="性别",
        choices=(
            (1, "男"),
            (2, "女")
        ),
        coerce=int
    )
    city = core.SelectField(
        label="城市",
        choices=(
            ("BJ", "北京"),
            ("SH", "上海"),
            ("GZ", "广州")
        )
    )
    hobby = core.SelectMultipleField(
        label="爱好",
        choices=(
            (1, "篮球"),
            (2, "足球")
        ),
        coerce=int
    )
    favor = core.SelectMultipleField(
        label="喜好",
        choices=(
            (1, "篮球"),
            (2, "足球"),
        ),
        widget=widgets.ListWidget(prefix_label=False),
        option_widget=widgets.CheckboxInput(),
        coerce=int,
        default=[1, 2]
    )

    def __init__(self, *args, **kwargs):
        """用于从数据库取出的数据是实时的"""
        super(RegisterForm, self).__init__(*args, **kwargs)
        self.favor.choices = ((1, "篮球"), (2, "足球"), (3, "羽毛球"))
        # self.favor.choices = 从数据库取到的数据

    def validate_password_confirm(self, field):
        """
        自定义password_confirm字段规则，例如：与password字段是否一致
        """
        # 最开始初始化时，self.data中已经有所有的值
        if field.data != self.data["password"]:
            # raise validators.ValidationError("密码不一致") # 继续后续验证
            raise validators.StopValidation("密码不一致")  # 不再继续后续验证

# {"password_confirm": ["两次密码输入不一致", "密码不一致"]}

@app.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "GET":
        form = RegisterForm(data={"gender": 1})
        return render_template("register.html", form=form)
    form = RegisterForm(formdata=request.form)
    if form.validate():
        print(form.data)
        return "注册成功"
    else:
        print(form.errors)
        return render_template("register.html", form=form)


if __name__ == "__main__":
    app.run()from flask import Flask, request, render_template
from wtforms import Form
from wtforms import widgets
from wtforms import validators
from wtforms.fields import core
from wtforms.fields import html5
from wtforms.fields import simple

app = Flask(__name__)


class RegisterForm(Form):
    username = simple.StringField(
        label="账号",
        validators=[
            validators.DataRequired(message="账号不能为空")
        ],
        widget=widgets.TextInput(),
        render_kw={"class": "c1"},
        default="pd"  # 默认值
    )
    password = simple.PasswordField(
        label="密码",
        validators=[
            validators.DataRequired(message="密码不能为空")
        ],
        widget=widgets.PasswordInput(),
        render_kw={"class": "c2"}
    )
    password_confirm = simple.PasswordField(
        label="重复密码",
        validators=[
            validators.DataRequired(message="重复密码不能为空"),
            validators.EqualTo("password", message="两次密码输入不一致")
        ],
        widget=widgets.PasswordInput(),
        render_kw={"class": "c3"}
    )
    email = html5.EmailField(
        label="邮箱",
        validators=[
            validators.DataRequired(message="邮箱不能为空"),
            validators.Email(message="邮箱格式错误")
        ],
        widget=widgets.TextInput(input_type="email"),
        render_kw={"class": "c4"}
    )
    gender = core.RadioField(
        label="性别",
        choices=(
            (1, "男"),
            (2, "女")
        ),
        coerce=int
    )
    city = core.SelectField(
        label="城市",
        choices=(
            ("BJ", "北京"),
            ("SH", "上海"),
            ("GZ", "广州")
        )
    )
    hobby = core.SelectMultipleField(
        label="爱好",
        choices=(
            (1, "篮球"),
            (2, "足球")
        ),
        coerce=int
    )
    favor = core.SelectMultipleField(
        label="喜好",
        choices=(
            (1, "篮球"),
            (2, "足球"),
        ),
        widget=widgets.ListWidget(prefix_label=False),
        option_widget=widgets.CheckboxInput(),
        coerce=int,
        default=[1, 2]
    )

    def __init__(self, *args, **kwargs):
        """用于从数据库取出的数据是实时的"""
        super(RegisterForm, self).__init__(*args, **kwargs)
        self.favor.choices = ((1, "篮球"), (2, "足球"), (3, "羽毛球"))
        # self.favor.choices = 从数据库取到的数据

    def validate_password_confirm(self, field):
        """
        钩子函数
        自定义password_confirm字段规则，例如：与password字段是否一致
        """
        # 最开始初始化时，self.data中已经有所有的值
        if field.data != self.data["password"]:
            # raise validators.ValidationError("密码不一致") # 继续后续验证
            raise validators.StopValidation("密码不一致")  # 不再继续后续验证

# {"password_confirm": ["两次密码输入不一致", "密码不一致"]}

@app.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "GET":
        form = RegisterForm(data={"gender": 1})
        return render_template("register.html", form=form)
    form = RegisterForm(formdata=request.form)
    if form.validate():
        print(form.data)
        return "注册成功"
    else:
        print(form.errors)
        return render_template("register.html", form=form)


if __name__ == "__main__":
    app.run()

app.py

<!DOCTYPE html>
<html lang="zh-cn">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form method="post" novalidate>
{% for field in form %}
    <div>{{ field.label }}{{ field }}{{ field.errors[0] }}</div>
{% endfor %}
<div><input type="submit" value="注册"></div>
</form>
</body>
</html>

Meta

import hashlib
from flask import Flask, request, render_template, redirect
from wtforms import Form
from wtforms.fields import simple
from wtforms.csrf.core import CSRF
app = Flask(__name__)


class MyCSRF(CSRF):
    """
    Generate a CSRF token based on the user"s IP. I am probably not very
    secure, so don"t use me.
    """
    def setup_form(self, form):
        self.csrf_context = form.meta.csrf_context()
        self.csrf_secret = form.meta.csrf_secret
        return super(MyCSRF, self).setup_form(form)

    def generate_csrf_token(self, csrf_token):
        gid = self.csrf_secret + self.csrf_context
        token = hashlib.md5(gid.encode("utf-8")).hexdigest()
        return token

    def validate_csrf_token(self, form, field):
        # print(field.data, field.current_token)
        if field.data != field.current_token:
            raise ValueError("Invalid CSRF")


class LoginForm(Form):
    username = simple.StringField(label="账号")
    password = simple.PasswordField(label="密码")

    class Meta:
        ########## CSRF ##########
        # 是否自动生成CSRF标签
        csrf = True
        # 生成CSRF标签name
        csrf_field_name = "csrf_token"
        # 自动生成标签的值，加密用的csrf_secret
        csrf_secret = "aa"
        # 自动生成标签的值，加密用的csrf_context
        csrf_context = lambda x: request.url
        # 生成和比较csrf标签
        csrf_class = MyCSRF

        ########## i18n ##########
        # 是否支持本地化
        # locales = False
        locales = ("zh", "en")
        # 是否对本地化进行缓存
        cache_translations = True
        # 保存本地化缓存信息的字段
        translations_cache = {}


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "GET":
        form = LoginForm()
        return render_template("login.html", form=form)
    form = LoginForm(formdata=request.form)
    if form.validate():
        print(form.data)
        return redirect("https://www.cnblogs.com/believepd/")
    else:
        print(form.errors)
        return render_template("login.html", form=form)


if __name__ == "__main__":
    app.run()

View Code

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原文地址：https://www.cnblogs.com/believepd/p/10362736.html