一、什么是wtforms
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。
安装：
pip3 install WTForms
二、简单使用wtforms组件
（一）用户登陆验证
py文件代码：
from flask import Flask,render_template,request,redirect from wtforms.fields import core from wtforms.fields import html5 from wtforms.fields import simple from wtforms import Form from wtforms import validators from wtforms import widgets app = Flask(__name__,template_folder="templates") class Myvalidators(object): '''自定义验证规则''' def __init__(self,message): self.message = message def __call__(self, form, field): print(field.data,"用户输入的信息") if field.data == "haiyan": return None raise validators.ValidationError(self.message) class LoginForm(Form): '''Form''' name = simple.StringField( label="用户名", widget=widgets.TextInput(), validators=[ Myvalidators(message="用户名必须是haiyan"),#也可以自定义正则 validators.DataRequired(message="用户名不能为空"), validators.Length(max=8,min=3,message="用户名长度必须大于%(max)d且小于%(min)d") ], render_kw={"class":"form-control"} #设置属性 ) pwd = simple.PasswordField( label="密码", validators=[ validators.DataRequired(message="密码不能为空"), validators.Length(max=8,min=3,message="密码长度必须大于%(max)d且小于%(min)d"), validators.Regexp(regex="d+",message="密码必须是数字"), ], widget=widgets.PasswordInput(), render_kw={"class":"form-control"} ) @app.route('/login',methods=["GET","POST"]) def login(): if request.method =="GET": form = LoginForm() return render_template("login.html",form=form) else: form = LoginForm(formdata=request.form) if form.validate(): print("用户提交的数据用过格式验证，值为：%s"%form.data) return "登录成功" else: print(form.errors,"错误信息") return render_template("login.html",form=form) if __name__ == '__main__': app.run(debug=True)
login.html：
<body> <form action="" method="post" novalidate> <p>{{ form.name.label }} {{ form.name }} {{ form.name.errors.0 }}</p> <p>{{ form.pwd.label }} {{ form.pwd }} {{ form.pwd.errors.0 }}</p> <input type="submit" value="提交"> <!--用户名：<input type="text">--> <!--密码：<input type="password">--> <!--<input type="submit" value="提交">--> </form> </body>
前端页面效果：
（二）用户注册验证
py文件代码：
from flask import Flask,render_template,redirect,request from wtforms import Form from wtforms.fields import core from wtforms.fields import html5 from wtforms.fields import simple from wtforms import validators from wtforms import widgets app = Flask(__name__,template_folder="templates") app.debug = True =======================simple=========================== class RegisterForm(Form): name = simple.StringField( label="用户名", validators=[ validators.DataRequired() ], widget=widgets.TextInput(), render_kw={"class":"form-control"}, default="haiyan" ) pwd = simple.PasswordField( label="密码", validators=[ validators.DataRequired(message="密码不能为空") ] ) pwd_confim = simple.PasswordField( label="重复密码", validators=[ validators.DataRequired(message='重复密码不能为空.'), validators.EqualTo('pwd',message="两次密码不一致") ], widget=widgets.PasswordInput(), render_kw={'class': 'form-control'} ) ========================html5============================ email = html5.EmailField( #注意这里用的是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': 'form-control'} ) ===================以下是用core来调用的======================= gender = core.RadioField( label="性别", choices=( (1,"男"), (1,"女"), ), coerce=int #限制是int类型的 ) city = core.SelectField( label="城市", choices=( ("bj","北京"), ("sh","上海"), ) ) 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): #这里的self是一个RegisterForm对象 '''重写__init__方法''' super(RegisterForm,self).__init__(*args, **kwargs) #继承父类的init方法 self.favor.choices =((1, '篮球'), (2, '足球'), (3, '羽毛球')) #吧RegisterForm这个类里面的favor重新赋值 def validate_pwd_confim(self,field,): ''' 自定义pwd_config字段规则，例：与pwd字段是否一致 :param field: :return: ''' # 最开始初始化时，self.data中已经有所有的值 if field.data != self.data['pwd']: # 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 @app.route('/register',methods=["GET","POST"]) def register(): if request.method=="GET": form = RegisterForm(data={'gender': 1}) #默认是1, return render_template("register.html",form=form) else: form = RegisterForm(formdata=request.form) if form.validate(): #判断是否验证成功 print('用户提交数据通过格式验证，提交的值为：', form.data) #所有的正确信息 else: print(form.errors) #所有的错误信息 return render_template('register.html', form=form) if __name__ == '__main__': app.run()
register.html：
<body> <h1>用户注册</h1> <form method="post" novalidate style="padding:0 50px"> {% for item in form %} <p>{{item.label}}: {{item}} {{item.errors[0] }}</p> {% endfor %} <input type="submit" value="提交"> </form> </body>
前端页面效果：
