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。
Refer to the following articles to check how to create a project and an app in Django.
- How to Create a Basic Project using MVT in Django?
- How to Create an App in Django ?
在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。
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
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 Options | Description |
|---|---|
| required | By default, each Field class assumes the value is required, so to make it not required you need to set required=False |
| label | The label argument lets you specify the “human-friendly” label for this field. This is used when the Field is displayed in a Form. |
| label_suffix | The label_suffix argument lets you override the form’s label_suffix on a per-field basis. |
| widget | The widget argument lets you specify a Widget class to use when rendering this Field. See Widgets for more information. |
| help_text | The 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_messages | The 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. |
| validators | The validators argument lets you provide a list of validation functions for this field. |
| localize | The 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. |
在评论中写代码？请使用 ide.geeksforgeeks.org，生成链接并在此处分享链接。