form component properties
- Data validation function
- Generate HTML code
Reference form component module
from django import forms #Introducing forms module from django.forms import fields
data validation
Validation type
| Data validation type | Data validation method |
|---|---|
| String validation | Fields.charfield (validation parameter) |
| Integer Digital Verification | Fields.integerfield (validation parameter) |
| Mailbox validation | Fields.emailfield (validation parameter) |
Validation parameters
| Data validation parameters | Interpretation |
|---|---|
| required=True, | Is it a null limit |
| max_length=8, | Maximum length limit |
| min_length=8, | Minimum length limit |
| invalid | Format error, only used in error message |
Custom error message
error_messages={"Validation parameters":"Custom error message"}
form validation instance
Create project
django-admin startproject Mydjango cd Mydjango python manage.py startapp APP
Project framework
[others remain the default ignore not shown]
Mydjango APP static jquery-3.3.1.min.js templates login01.html views.py Mydjango settings.py urls.py
login01.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>this from login_01</title> <script src="../static/jquery-3.3.1.min.js"></script> <style> form i{color: red;} </style> </head> <body> <form action="login01.html" method="POST"> {% csrf_token %} <!--Explanation:--> <!--HTML Page generation--> <!--{{ obj.user }} Fetching from back-end data, using forms Module generation user user input Other labels are similar--> <!--Error message feedback--> <!--{{ data_obj }} For all data sent to the back end--> <!--{{ data_obj.user }} For delivery to the back end, user Data for field--> <!--{{ data_obj.user.cleaned_data }} For delivery to the back end, user Data passed field validation--> <!--{{ data_obj.user.cleaned_errors }} For delivery to the back end, user Error message feedback of field validation failure, there may be multiple error messages--> <!--{{ data_obj.user.cleaned_errors.0 }} For delivery to the back end, user First error message fed back by error message of field validation failure--> <!--Similar to other fields--> <p>User:{{ obj.user }}<i>{{ data_obj.user.errors.0 }}</i></p> <p>Password:{{ obj.pwd }}<i>{{ data_obj.pwd.errors.0 }}</i></p> <p>Age:{{ obj.age }}<i>{{ data_obj.age.errors.0 }}</i></p> <p>Mailbox:{{ obj.email }}<i>{{ data_obj.email.errors.0 }}</i></p> <p><a><input type="submit" value="Submission"></a></p> </form> <script> </script> </body> </html>
views.py
# -*- coding:utf8 -*- from django.shortcuts import render,HttpResponse from django import forms #Introducing forms module from django.forms import fields class From_submit(forms.Form): #Inherit forms module #Use the froms module to verify the data, and keep the variable name consistent with the front-end name attribute # Start ------------- forms module data validation------------------------------ # Limit type - string maximum length minimum length, and cannot be empty user = fields.CharField( max_length=18, min_length=3, required=True, error_messages={ 'required':'User name cannot be empty', 'max_length':'User name cannot exceed 18 characters', 'min_length':'User name cannot be less than 3 characters', } ) # Restriction type - string minimum length is 8 and cannot be empty pwd = fields.CharField( max_length=32, min_length=8, required=True, error_messages = { 'required': 'Password cannot be empty', 'max_length': 'Password cannot exceed 32 characters', 'min_length': 'Password cannot be less than 8 characters', } ) # Restriction type - integer, and cannot be empty age = fields.IntegerField( required=True, error_messages={ 'required': 'Age cannot be empty', 'invalid':'There is a problem with the age format, it must be a number', } ) # Restriction type - mailbox, and cannot be empty email = fields.EmailField( required=True, error_messages={ 'required': 'Mailbox cannot be empty', 'invalid': 'There is a problem with the mailbox format', } ) # End ------------- forms module data validation------------------------------ def Data_sub(request): if request.method == "POST": data_obj = From_submit(request.POST) #Get all the data from if data_obj.is_valid(): #Judge whether the verification is successful print("Validation successful:",data_obj.cleaned_data) #The correct data of the user after successful verification [dictionary form] return HttpResponse("Submitted successfully!!!") else: print("Validation error:",data_obj.errors) #Error message returned from validation failure return render(request,"login01.html",{"data_obj":data_obj}) #Transfer the validation data to the front-end page for easy access to the data passing the validation and error feedback information else: obj = From_submit() #Submission data with error information return render(request, "login01.html",{"obj":obj}) #Error message and submitted data return to submission page
urls.py
from django.contrib import admin from django.urls import path,re_path from APP import views urlpatterns = [ path('admin/', admin.site.urls), re_path('^login01.html$',views.Data_sub), ]
settings.py
INSTALLED_APPS = [ 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', 'APP', ]
TEMPLATES = [ { 'BACKEND': 'django.template.backends.django.DjangoTemplates', 'DIRS': [os.path.join(BASE_DIR, 'APP/templates')], 'APP_DIRS': True, 'OPTIONS': { 'context_processors': [ 'django.template.context_processors.debug', 'django.template.context_processors.request', 'django.contrib.auth.context_processors.auth', 'django.contrib.messages.context_processors.messages', ], }, }, ]
Operation test
python manage.py runserver