django之form表单验证-白红宇

django之form表单验证

阅读量：7153 次

发布时间：2019-06-29

本文共 5826 字，大约阅读时间需要 19 分钟。

form组件的校验功能

views.py

from django.shortcuts import render, HttpResponse# Create your views here.from django import formsfrom django.forms import widgetsclass UserForm(forms.Form):    name = forms.CharField(min_length=4,label='用户名') # 必须用required    pwd = forms.CharField(min_length=4,label='密码')    r_pwd = forms.CharField(min_length=4,label='确认密码')    email = forms.EmailField(label='邮箱')    tel = forms.CharField(label='手机')def reg(request):    if request.method == 'POST':        # form = UserForm({'name': 'ed', 'email': '123@qq.com'})  # 加多少个键值都无所谓，只要能匹配全Form里的字段就会返回True        # print(form.is_valid())  # 返回布尔值                form = UserForm(request.POST)  # form表单的name属性值应该与forms组件字段名称一致        if form.is_valid():            print(form.changed_data)  # 存的是通过校验的字典        else:            print(form.cleaned_data)  # {正确的键值,"email":"123@11.com"}            print(form.errors)  # {"name":["insure this value has at least 4 characters]}            print(type(form.errors))  # ErrorDict            print(form.errors.get('name'))            print(type(form.errors.get('name')))  # ErrorList            print(form.errors.get('name')[0])  # This field is required.        '''        if 所有字段校验成功，则form.cleaned_data：{'name': 'edward', 'email': '123@qq.com'}        '''        return render(request, 'register.html', locals())    form = UserForm()   # get请求的form，渲染form组件用    return render(request, 'register.html', locals())

html


     
          {% csrf_token %}    
      用户名：
    
      密码：
    
      确认密码：
    
      邮箱：
    
      手机号：

form组件渲染的三种方式

form组件渲染方式1
     
          {% csrf_token %}    
      {
   { form.name.label }}：{
   { form.name }} {
   { form.name.errors.0 }}
    
      {
   { form.pwd.label }}：{
   { form.pwd }} {
   { form.pwd.errors.0 }}
    
      {
   { form.r_pwd.label }}：{
   { form.r_pwd }} {
   { form.r_pwd.errors.0 }}
    
      {
   { form.email.label }}：{
   { form.email }} {
   { form.email.errors.0 }}
    
      {
   { form.tel.label }}：{
   { form.tel }} {
   { form.tel.errors.0 }}
    
      
     
     
form组件渲染方式2
     
          {% csrf_token %}    {% for filed in form %}        
                  {
   { filed.label }}            {
    { filed }}        
    {% endfor %}    
      
     
     
form组件渲染方式3 --- 不建议使用这种方式，因为它只能固定放那么几个标签，缺乏灵活性，以后改动麻烦
     
          {% csrf_token %}    {
    { form.as_p }}

显示错误信息和参数配置

class UserForm(forms.Form):    name = forms.CharField(min_length=4, label='用户名',                           error_messages={
   "required": "该字段不能为空"},                           widget=widgets.TextInput(attrs={
   'class': 'form-control'})                           )  # 必须用要提示错误信息的关键词    pwd = forms.CharField(min_length=4, label='密码',                          widget=widgets.PasswordInput(attrs={
   'class': 'form-control'}),                          error_messages={                              "required": "该字段不能为空"                          })    r_pwd = forms.CharField(min_length=4, label='确认密码',                            error_messages={
   "required": "该字段不能为空"},                            widget=widgets.PasswordInput(attrs={
   'class': 'form-control'}),                            )    email = forms.EmailField(label='邮箱',                             error_messages={
   "required": "该字段不能为空", 'invalid': "格式错误"},                             widget=widgets.TextInput(attrs={
   'class': 'form-control'}),                             )    tel = forms.CharField(label='手机',                          error_messages={
   "required": "该字段不能为空", },                          widget=widgets.TextInput(attrs={
   'class': 'form-control'}),                          )

局部钩子

def clean_name(self):        val = self.cleaned_data.get('name')        ret = UserInfo.objects.filter(name=val)        if not ret:            return val        else:            raise ValidationError('该用户已注册!')                         def clean_tel(self):    val = self.cleaned_data.get('tel')    ret = UserInfo.objects.filter(tel=val)    if len(ret) == 11:        return val    else:        raise ValidationError('手机号格式错误')            # 源码def _clean_fields(self):    try:        if isinstance(field, FileField):            initial = self.get_initial_for_field(field, name)            value = field.clean(value, initial)        else:            value = field.clean(value)        self.cleaned_data[name] = value        if hasattr(self, 'clean_%s' % name):            value = getattr(self, 'clean_%s' % name)()            self.cleaned_data[name] = value     except ValidationError as e :        self.add_error(name, e)

全局钩子

为了解耦，新建一个myforms.py的文件，把有关forms的代码都放在这里面。

# 全局钩子# 走完所有的校验才走cleandef clean(self):    # 走完所有的校验才走clean    pwd = self.cleaned_data.get('pwd')    r_pwd = self.cleaned_data.get('r_pwd')        # 都满足不低于4个字符这个条件后才验证密码是否一致    if pwd and r_pwd:        if pwd == r_pwd:            return self.cleaned_data        else:            raise ValidationError('两次密码不一致')            else:                return self.cleaned_data        #源码def clean(self):    """    Hook for doing any extra form-wide cleaning after Field.clean() has been    called on every field. Any ValidationError raised by this method will    not be associated with a particular field; it will have a special-case    association with the field named '__all__'.    """    return self.cleaned_datadef _clean_form(self):    try:        cleaned_data = self.clean()    except ValidationError as e:        self.add_error(None, e)    else:        if cleaned_data is not None:            self.cleaned_data = cleaned_data                        # 全局钩子在前端没有显示，要在处理post请求的代码里给错误信息一个变量并传到前端errors = form.errors.get('__all__')# 当两次密码不一致时，在前端显示这个错误    {
    { form.r_pwd.label }}：{
    { form.r_pwd }}    {
   { form.r_pwd.errors.0 }}    {
   { errors.0 }}