python-wtforms框架如何自定义校验器的原理和方法总结

忘是亡心i 2021-09-18 01:00 397阅读 0赞

### **wtforms框架官方关于自定义校验器的参考：[https://wtforms.readthedocs.io/en/stable/validators.html\#setting-flags-on-the-field-with-validators][https_wtforms.readthedocs.io_en_stable_validators.html_setting-flags-on-the-field-with-validators] ** ###

**细节请看注释，核心就是\_\_call\_\_函数的用法（def \_\_call\_\_(self,form, field)参数由继承的Form自动提供）**

### **\_\_call\_\_函数，**当实例作为函数“调用”时调用；【比如：MyValidators类的实例对象是my = MyValidators(),那么调用my()函数--把实例对象my当做函数调用的时候，会调用\_\_call\_\_】 ###

from wtforms import Form, StringField, validators, PasswordField,ValidationError
    
    
    #wtforms自定义校验器参考格式
    class MyValidators(Form):
        def __init__(self):
            pass
    
        #__call__函数创建对象之后，系统自动调用,变量from(校验器)和field(字段)分别由wtforms的From自动提供！
        def __call__(self,form, field):
            if len(str(field.data)) > 8:
                raise ValidationError("自定义校验器有错误出现")
    
    
    
    class RegisterForm(Form):
        email = StringField("email", validators=[validators.Email("邮件格式错误,请重新输入...")])
        password = PasswordField("password", validators=[validators.Length(min=6, max=16,message = "密码长度必须为6-16位" ),
                                                         MyValidators()])
    
    
    reg = RegisterForm(data={"email":"528185681@qq.com","password":"D56234455"})
    reg.validate()
    
    a = 1

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[https_wtforms.readthedocs.io_en_stable_validators.html_setting-flags-on-the-field-with-validators]: https://wtforms.readthedocs.io/en/stable/validators.html#setting-flags-on-the-field-with-validators
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