First, the original registration check
# Rear DEF realreg (Request): error = { ' username ' : '' , ' password ' : '' } # define a dictionary storage error IF request.method == ' the POST ' : username = request.POST.get ( ' username ' ) password = request.POST.get ( ' password ' ) IF len (password) <. 6 : error [ ' password '] = '密码不能小于6位' return render(request,'reg.html',{'error':error}) # 前端 <input type='text' name='username'> <span>{{ error.username }}</span> <input type='text' name='password'> <span>{{ error.password }}</span>
- Front-end interface is registered, there are a form page Form >>> generate HTML front-end code
- form form to be able to submit data to the back-end, back-end do check the validity of data validity checking >>>
- Message should check presentation to the page >>> back and check information display
Inspection data regarding: a front end by JS code check (optional), a rear end through code checking (must), front and rear ends generally do check.
Two, form components
2.1 features
- Render tag
- Check data
- Display information
- Check information
2.2 form class
Step One: Custom form a class
from django import forms class MyForm(forms.Form): name = forms.CharField(max_length=6) password = forms.CharField(max_length=8,min_length=3) email = forms.EmailField(required=True)
Step Two: form objects instantiated
= the MyForm form_obj ({ ' name ' : ' moonzier ' , ' password ' : ' 123 ' , ' In Email ' : ' [email protected] ' }) # incoming Dictionary
Step Three: Check the legality of data validation
form_obj.is_valid () # Only when all fields are by check will return True
Step Four: Check validation error message
form_obj.errors # which put a field error and does not pass the checksum of all "" " { 'name': [ 'Ensure® AT MOST has the this value. 6 characters (IT has. 7).'], 'password': [ '. Ensure® Least AT has the this value. 3 characters (IT has 2)'], 'In Email': [ 'the Enter A Valid In Email address.'] } "" "
Step Five: Check the data validation through
form_obj.cleaned_data # compliance with data validation rules will be put in the object
Rule check data form component
- Down sequentially from the value of the parity
- The check is passed into cleaned_data
- Validation failure into errors
- All form fields must pass all default values (required = True)
- Check data when you can pass (multi-pass data will not do any checking, validation rules will not affect the form)
# Distal canceled check <form Action = "" Method = " POST " NOVALIDATE> </ form>
2.3 rendering label
form components only render help you get the label entered by the user, will not help you render the submit button, you need to add manually.
The first: poor scalability
Form_obj.as_p} {} { <-! A <p> tag rendered in ->
{} {} form_obj.as_ul
The second: one by handwriting
< Form Action = "" > < P > {{{{form_obj.name form_obj.name.label}}}} </ P > <-! If the rear end of the name attribute is not defined, then the field is the first letter capitalized as the label value -> < P > {{{{form_obj.password form_obj.password.label}}}} </ P > < P > {{{{form_obj.email form_obj.email.label}}}} < / P > < INPUT type = "Submit" > </ form >
Third: for loop
<form action=""> {% for foo in form_obj %} <p>{{ foo.label }}{{ foo }}</p> {% endfor %} </form>
2.4 Settings tab style
When the form definition of the class, which is provided in the pattern field.
from Django Import Forms from `` django.forms`` Import Widgets password = forms.CharField (= MAX_LENGTH. 8 , min_length =. 3 , error_messages, = { ' MAX_LENGTH ' : ' maximum password 8 ' , ' required ' : ' password can not be empty ' , ' min_length ' : ' password least three' }, The widget = widgets.PasswordInput (attrs = { ' class ' : ' C1-Control form ' })) # widgets.PasswordInput password in ciphertext, attr increase the field
Integrated Case
# Rear # define form class class the MyForm (forms.Form): name = forms.CharField (MAX_LENGTH =. 6 , label = ' username ' , # distal label tag label attribute values obtained error_messages, = { ' MAX_LENGTH ' : ' username longest 6 ' , ' required ' : ' a user name can not be empty ' } #Custom error message, can be changed into Chinese ) DEF REG (Request): # generates an empty object form_obj = the MyForm () IF request.method == ' the POST ' : form_obj = the MyForm (of request.POST) # of request.POST is a dictionary, automatically checking incoming data, and a data error occurs is not clear IF form_obj.is_valid (): models.User.objects.create ( ** form_obj.cleaned_data) # using the model table form component data checking time, just to ensure consistent field so when you create an object directly ** form_obj.cleaned_data return the render (Request, ' reg.html ' , about locals ())
# 前端 <form action="" method="post" novalidate> {% for foo in form_obj %} <p> {{ foo.label }}{{ foo }} <span>{{ foo.errors.0 }}</span> #只取第一个错误 </p> {% endfor %} <input type="submit"> </form>
Third, the hook function
Local hook function (a single field using local parity hook function)
# Check the name field 666 appears on the error if DEF clean_name (Self): name = self.cleaned_data.get ( ' name ' ) IF ' 666 ' in name: self.add_error ( ' name ' , ' light is not enough to call 666 , there must be a real force! ' ) return name # return or to add, compatibility considerations
Global hook function (by using a plurality of verification fields global hook function)
# Parity on password and confirm_password consistent, error is inconsistent DEF Clean (Self): password = self.cleaned_data.get ( ' password ' ) confirm_password = self.cleaned_data.get ( ' confirm_password ' ) IF Not password == confirm_password: Self .add_error ( ' confirm_password ' , " two passwords do not match! " ) return self.cleaned_data