1. Introduction to the Form component
1. Several things that the Form component can do
1. User requests data verification
2. Automatically generate error messages
3. Pack the correct information submitted by users
4. If one of them is wrong, the others are correct, keep the last input
5. Automatically create input tags and can set styles
2. Django built-in fields are as follows
Field
required = True, #Whether it is allowed to be empty
widget = None, #HTML plugin
label = None, #Used to generate Label labels or display content
initial = None, #initial value
help_text = '', #help information (displayed next to the label)
error_messages = None, #Error message{'required': 'cannot be empty', 'invalid': 'format error'}
show_hidden_initial = False, #Whether to add a hidden plug-in with default value after the current plug-in (can be used to check whether the two inputs are consistent)
validators = [], #custom validation rules
localize = False, #Whether to support localization
disabled = False, #Whether it can be edited
label_suffix = None #Label content suffix
CharField(Field)
max_length = None, #maximum length
min_length = None, #minimum length
strip = True #whether to remove user input blanks
IntegerField(Field)
max_value = None, #Maximum value
min_value = None, #minimum
DecimalField(IntegerField)
max_value = None, #Maximum value
min_value = None, #minimum
max_digits = None, #total length
decimal_places = None, #length of decimal places
BaseTemporalField(Field)
input_formats = None # time formatting
DateField(BaseTemporalField) #格式：2015 - 09 - 01
TimeField(BaseTemporalField) # Format: 11: 12
DateTimeField(BaseTemporalField) #格式：2015 - 09 - 01 11: 12
DurationField(Field) #time interval: % d % H: % M: % S. % f
...
RegexField(CharField)
regex, #custom regular expression
max_length = None, #maximum length
min_length = None, #minimum length
error_message = None, #Ignore, use error_messages = {'invalid': '...'} for error messages
FileField(Field)
allow_empty_file = False #Whether empty files are allowed
ChoiceField(Field)
...
choices = (), #Options, such as: choices = ((0, 'Shanghai'), (1, 'Beijing'),)
required = True, #required
widget = None, #plugin, the default plugin is selected
label = None, #Label content
initial = None, #initial value
help_text = '', #help hint
ModelChoiceField(ChoiceField)
... django.forms.models.ModelChoiceField
queryset, # query the data in the database
empty_label = "---------", # default empty display content
to_field_name = None, # Field corresponding to the value of value in HTML
limit_choices_to = None # Secondary filtering of queryset in ModelForm
ModelMultipleChoiceField(ModelChoiceField)
... django.forms.models.ModelMultipleChoiceField
TypedChoiceField(ChoiceField)
coerce = lambda val: val #Convert the selected value once
empty_value = '' # default value for empty value
TypedMultipleChoiceField(MultipleChoiceField)
coerce = lambda val: val #Convert once for each selected value
empty_value = '' #default value of empty value
ComboField(Field)
fields = () #Use multiple validations, as follows: that is to validate the maximum length of 20, and validate the mailbox format fields.ComboField(fields=[fields.CharField(max_length=20), fields.EmailField(), ])
SplitDateTimeField(MultiValueField)
input_date_formats = None, #Format list: ['%Y--%m--%d', '%m%d/%Y', '%m/%d/%y']
input_time_formats = None #Format list: ['%H:%M:%S', '%H:%M:%S.%f', '%H:%M']
FilePathField(ChoiceField) #File options, the files in the directory are displayed on the page
path, #folder path
match = None, #regular match
recursive = False, #recursive folders below
allow_files = True, #Allow files
allow_folders = False, #Allow folders
required = True,
widget = None,
label = None,
initial = None,
help_text = ''
GenericIPAddressField
protocol = 'both', both, ipv4, ipv6 supported IP formats
unpack_ipv4 = False parses ipv4 address, if it is ::ffff: 192.0.2.1, it can be parsed as 192.0.2.1, PS: protocol must be both to enable
3. Commonly selected plugins
# single radio, the value is a string user = fields.CharField( initial=2, widget=widgets.RadioSelect(choices=((1,'Shanghai'),(2,'Beijing'),)) ) # single radio, the value is a string user = fields.ChoiceField( choices=((1, 'Shanghai'), (2, 'Beijing'),), initial=2, widget=widgets.RadioSelect ) # Single select, the value is a string user = fields.CharField( initial=2, widget=widgets.Select(choices=((1,'Shanghai'),(2,'Beijing'),)) ) # Single select, the value is a string user = fields.ChoiceField( choices=((1, 'Shanghai'), (2, 'Beijing'),), initial=2, widget=widgets.Select ) # Multi-select select, the value is a list user = fields.MultipleChoiceField( choices=((1,'Shanghai'),(2,'Beijing'),), initial=[1,], widget=widgets.SelectMultiple ) # Single checkbox user = fields.CharField( widget=widgets.CheckboxInput() ) # Multi-select checkbox, the value is a list user = fields.MultipleChoiceField( initial=[2, ], choices=((1, 'Shanghai'), (2, 'Beijing'),), widget=widgets.CheckboxSelectMultiple )
2. Form rendering registration page
views.py file content:
from django.shortcuts import render,HttpResponse
from django import forms
from django.forms import widgets
class UserForm(forms.Form):
user=forms.CharField(label="username",
min_length=5,
error_messages={"required":"cannot be empty","min_length":"minimum length cannot be less than 5"},
widget=widgets.TextInput(attrs={"class":"form-control"})
)
tel=forms.CharField(label="手机号",max_length=8, widget=widgets.TextInput(attrs={"class":"form-control"}))
email=forms.EmailField(label="邮箱", widget=widgets.TextInput(attrs={"class":"form-control"}))
def reg(request):
if request.method=="POST":
#form=UserForm({"user":"alex999","tel":'123',"email":"111","123":123})
form=UserForm(request.POST)
if form.is_valid():
print("====>",form.cleaned_data) # Fields successfully verified {"user":"alex999","tel":'123'}
print("====>",form.errors) # Verify failed fields
return HttpResponse("Added successfully")
else:
# print("---->", form.cleaned_data) #
# print("---->", type(form.errors)) # <class 'django.forms.utils.ErrorDict'>
# print("---->", type(form.errors["user"])) #
# print("---->", form.errors["user"][0]) #
return render(request, 'reg.html',{"form":form})
form=UserForm()
return render(request,'reg.html',{"form":form})
reg.html file content:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Title</title>
<style>
span{
color: red!important;
}
</style>
<link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
{#####################################Option One:######### ##############################}
<div>
<div>
<div class="col-md-6 col-md-offset-3">
<form action="" method="post" novalidate>
{% csrf_token %}
{% for filed in form %}
<div>
<label for="">{{ filed.label }}</label>
{{ filed }}
</div>
{% endfor %}
<input type="submit">
</form>
</div>
</div>
</div>
{#####################################Option II:######### ##############################}
<div>
<div>
<div class="col-md-6 col-md-offset-3">
<form action="" method="post" novalidate>
{% csrf_token %}
<div>
username:
{{ form.user }}
</div>
<div>
Mail:
{{ form.email }}
</div>
<div>
Phone number:
{{ form.tel }}
</div>
<input type="submit">
</form>
</div>
</div>
</div>
{#####################################third solution:######### ##############################}
<div>
<div>
<div class="col-md-6 col-md-offset-3">
<form action="" method="post" novalidate>
{% csrf_token %}
{{ form.as_p }}
<input type="submit">
</form>
</div>
</div>
</div>
</body>
</html>
3. Examples
views.py file content:
from django.shortcuts import render,redirect
from app01 import models
from django.forms import Form
from django.forms import fields
from django.forms import widgets
class TeacherForm(Form): #Must inherit Form
username = fields.CharField(
required=True, #Required field
error_messages={"required":"Username cannot be empty!!"}, #Display Chinese error message
widget=widgets.TextInput(attrs={"placeholder":"username","class":"form-control"}) #Automatically generate input box
)
password = fields.CharField(required=True, error_messages={'required': 'Password cannot be empty'},
widget=widgets.TextInput(attrs={'placeholder': 'password', 'class': 'form-control'})) # cannot be empty
email = fields.EmailField(
required=True,
error_messages={"required":"The mailbox cannot be empty!!","invalid":"Invalid mailbox"},
widget=widgets.EmailInput(attrs={"placeholder": "mailbox", "class": "form-control"}) # Automatically generate input box
) #Cannot be empty and the mailbox format must be consistent
def teacherindex(request):
teacher_obj = models.UserInfo.objects.all()
return render(request,"teacherindex.html",{"teacher_obj":teacher_obj})
def add(request):
if request.method=="GET":
form = TeacherForm() # just show an input box
return render(request,"add.html",{"form":form })
else:
form = TeacherForm(data=request.POST)
# print(form) #<QuerySet [<UserInfo: UserInfo object>, <UserInfo: UserInfo object>, <UserInfo: UserInfo object>]>
if form.is_valid(): # start validation
# print('executed successfully', form.cleaned_data) # All matches are successful, dictionary
form.cleaned_data['ut_id'] = 1 #It is necessary to distinguish whether it is a class teacher or a lecturer
models.UserInfo.objects.all().create(**form.cleaned_data)
return redirect("/teacherindex/")
else:
# print("======?",form.errors,type(form.errors))#Return the result of failure
# print(form.errors["username"][0]) #Get the result of the return failure and render it to the page
return render(request,"add.html",{"form":form})
Front-end html page:
{% block right %}
<h1>Add teacher information</h1>
<hr>
<form method="post" novalidate>
{% csrf_token %}
<p>姓名：{{ form.username }}</p>{{ form.errors.username.0 }}
<p>密码：{{ form.password }}</p>{{ form.errors.password.0 }}
<p>邮箱：{{ form.email }}</p>{{ form.errors.email.0 }}
<p><input type="submit" value="提交"></p>
</form>
{% endblock %}