📜  初始 - Django 表单字段验证

📅  最后修改于: 2022-05-13 01:55:05.341000             🧑  作者: Mango

初始 - Django 表单字段验证

Django 表单中的内置表单字段验证是为所有字段预定义的默认验证。每个字段都带有来自 Django 验证器的一些内置验证。每个 Field 类的构造函数都有一些固定的参数。

initial用于在未绑定的表单中呈现此字段时更改输入标签中字段的值。 initial 接受作为字段新值的字符串作为输入。字段的默认首字母为空。让我们检查如何在使用项目的字段中使用初始值。

句法

field_name = models.Field(option = value)

Django 表单字段验证initial说明

初始使用示例的说明。考虑一个名为geeks的项目,它有一个名为geeksforgeeks的应用程序。

geeks app的forms.py文件中输入以下代码。我们将使用 CharField 来试验所有字段选项。

from django import forms
  
class GeeksForm(forms.Form):
    geeks_field = forms.CharField(initial = "Enter your Name")

将极客应用添加到INSTALLED_APPS

# Application definition
  
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'geeks',
]

现在要将这个表单渲染到一个视图中,我们需要一个视图和一个映射到该视图的 URL。我们先在geeks app的views.py中创建一个视图,

from django.shortcuts import render
from .forms import GeeksForm
  
# Create your views here.
def home_view(request):
    context = {}
    form = GeeksForm(request.POST or None)
    context['form'] = form
    if request.POST:
        if form.is_valid():
            temp = form.cleaned_data.get("geeks_field")
            print(temp)
    return render(request, "home.html", context)

在这里,我们从 forms.py 导入该特定表单并在视图中创建它的对象,以便可以在模板中呈现它。
现在,要启动一个 Django 表单,您需要创建 home.html,在其中可以根据需要设计内容。让我们在home.html中创建一个表单。

    {% csrf_token %}     {{ form }}     

最后,在 urls.py 中映射到该视图的 URL

from django.urls import path
  
# importing views from views..py
from .views import home_view
  
URLpatterns = [
    path('', home_view ),
]

让我们运行服务器并检查实际发生了什么,运行

Python manage.py runserver

初始——Django-Form-Field-Validation

因此,一个geeks_field CharField是用初始的“输入你的名字”创建的。

更多内置表单验证

Field OptionsDescription
requiredBy default, each Field class assumes the value is required, so to make it not required you need to set required=False
labelThe label argument lets you specify the “human-friendly” label for this field. This is used when the Field is displayed in a Form.
label_suffixThe label_suffix argument lets you override the form’s label_suffix on a per-field basis.
widgetThe widget argument lets you specify a Widget class to use when rendering this Field. See Widgets for more information.
help_textThe help_text argument lets you specify descriptive text for this Field. If you provide help_text, it will be displayed next to the Field when the Field is rendered by one of the convenience Form methods.
error_messagesThe error_messages argument lets you override the default messages that the field will raise. Pass in a dictionary with keys matching the error messages you want to override.
validatorsThe validators argument lets you provide a list of validation functions for this field.
localizeThe localize argument enables the localization of form data input, as well as the rendered output.
disabled.The disabled boolean argument, when set to True, disables a form field using the disabled HTML attribute so that it won’t be editable by users.