Flask_WTForms源码流程(糙版)

from flask import Flask, render_template, request, redirect

# Form
#    _fields
#    validate
#    validata_name
#    validata_pwd
from wtforms import Form

# 字段（通过正则进行校验；插件生成HTML标签）
#   - 插件对象
#   - post_validate
#   - __call__
#   - __str__
from wtforms.fields import core
from wtforms.fields import html5
from wtforms.fields import simple

# 插件
#    __call__返回：<input />
from wtforms import widgets

from wtforms import validators


app = Flask(__name__, template_folder='templates')
app.debug = True

"""
LoginForm._unbound_fields = None
LoginForm._wtforms_meta = None
"""
class LoginForm(Form):
    # name = UnboundField(StringField, *args, **kwargs) creation_counter=1
    name = simple.StringField(
        label='用户名',
        validators=[
            validators.DataRequired(message='用户名不能为空.'),
            validators.Length(min=6, max=18, message='用户名长度必须大于%(min)d且小于%(max)d')
        ],
        widget=widgets.TextInput(),
        render_kw={'class': 'form-control'}
    )
    # pwd = UnboundField(PasswordField, *args, **kwargs) creation_counter=2
    pwd = simple.PasswordField(
        label='密码',
        validators=[
            validators.DataRequired(message='密码不能为空.'),
            validators.Length(min=8, message='用户名长度必须大于%(min)d'),
            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={'class': 'form-control'}
    )

    class Meta:
        csrf = False

    def validate_pwd(self,*args,**kwargs):
        pass
# 解释到这里...




@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'GET':
        # type.__call__
        #   LoginForm._unbound_fields 已经有值(所有字段)   [(name,_unbound_fields()),(name,_unbound_fields()),]
        #   LoginForm._wtforms_meta = 类(Meta)（所有的Meta）
        #   LoginForm._wtforms_meta = type('Meta', tuple(bases), {})

        # LoginForm.__new__
        # LoginForm.__init__
        #    示例化Meta: meta_obj{name = 'alex','xx':'xxx'}
        #    self._fields = {
        #       name = StringField()
        #       pwd = PasswordField()
        #   }
        #   self.name =  StringField()
        #   self.pwd =  PasswordField()
        # class User:
        #     def __init__(self,name):
        #         self.name = name
        # obj = User('alex')

        # form = LoginForm(data={'name':'alex'})
        # form = LoginForm(obj=obj) #
        # form = LoginForm(formdata=request.args)
        # 页面标签数据初始化：data=字典, obj=对象.字段  formdata=有getlist方法
        form = LoginForm()
        # print(form.name)
        return render_template('login.html', form=form)
    else:
        form = LoginForm(formdata=request.form)
        if form.validate():
            print('用户提交数据通过格式验证，提交的值为：', form.data)
        else:
            print(form.errors)
        return render_template('login.html', form=form)

def test():
    form = LoginForm()




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