代码下载：/Files/maplye/django/Study914.rar
Manipulator英语翻译成“操纵器”，你可以用它来创建，修改，验证你的一个实体对象，并结合FormWrapper可以自动生成页面上Html代码（注：FormWrapper是用来生成html代码，Manipulator使为FormWrapper提供数据和数据模型等）。
Manipulator英语翻译成“操纵器”，你可以用它来创建，修改，验证你的一个实体对象，并结合FormWrapper可以自动生成页面上Html代码（注：FormWrapper是用来生成html代码，Manipulator使为FormWrapper提供数据和数据模型等）。
django系统已经带有两种Manipulator，一是AddManipulator，二是ChangeManipulator，我以前一直以为这是model的两个方法，还有ChangeManipulator我以为是为我的model更换一个Manipulator,其实他是两个不同的类。这两个类能够自动根据model来生成validation和save。AddManipulator和ChangeManipulator都是继承自Manipulator，不同的是ChangeManipulator带有一objectid的构造参数，并获取一object赋值给他的original_object属性，并在save方法使用修改对象，然后保存该对象。
关于这两种Manipulator的使用，可以参考django document:
除了django提供的两种Manipulator,我们还可以自定义Manipulator,这样我们定义自己的fields,validation,save等等。
如：
from django import forms
urgency_choices = (
(1, "Extremely urgent"),
(2, "Urgent"),
(3, "Normal"),
(4, "Unimportant"),
)
class ContactManipulator(forms.Manipulator):
def __init__(self):
self.fields = (
forms.EmailField(field_name="from", is_required=True),
forms.TextField(field_name="subject", length=30, maxlength=200, is_required=True),
forms.SelectField(field_name="urgency", choices=urgency_choices),
forms.LargeTextField(field_name="contents", is_required=True),
)
def save(self): #
.
而且我们还可以定义带有初始化参数的custom Manipulator
如：
class ContactManipulator(forms.Manipulator):
def __init__(self,object_id=None):
self.object_id = object_id
self.fields = (
forms.EmailField(field_name="fromEmail", is_required=True),
forms.TextField(field_name="subject", length=30, maxlength=200, is_required=True),
forms.SelectField(field_name="urgency", choices=urgency_choices),
forms.LargeTextField(field_name="contents", is_required=True),
)
def save(self, new_data):
fromemail = new_data["fromEmail"]
subject = new_data["subject"]
urgency = new_data["urgency"]
contents = new_data["contents"]
if self.object_id:
obj = Contact.objects.get(pk=int(self.object_id))
obj.fromEmail = fromemail
obj.subject = subject
obj.urgency = urgency;
obj.contents = contents;
else:
obj = Contact(fromEmail=fromemail, subject=subject, urgency=urgency,contents=contents)
obj.save()
你看上面ContactManipulator的Manipulator就具有AddManipulator和ChangeManipulator两个的功能，
那这个ContactManipulator应该怎么用呢
#创建
def contact_form(request):
manipulator = ContactManipulator()
if request.POST:
new_data = request.POST.copy()
errors = manipulator.get_validation_errors(new_data)
if not errors:
manipulator.do_html2python(new_data)
manipulator.save(new_data)
return HttpResponseRedirect("/formapp/contact/")
else:
errors = new_data = {}
form = forms.FormWrapper(manipulator, new_data, errors)
return render_to_response('places/contact_form.html', {'form': form})
#修改
def editcontact(request,contactid):
manipulator = ContactManipulator(contactid)
if request.POST:
new_data = request.POST.copy()
errors = manipulator.get_validation_errors(new_data)
if not errors:
manipulator.do_html2python(new_data)
manipulator.save(new_data)
# Do a post-after-redirect so that reload works, etc.
return HttpResponseRedirect("/formapp/contact/1")
else:
errors = {}
contact = Contact.objects.get(id = contactid)
new_data = contact.__dict__
form = forms.FormWrapper(manipulator, new_data,errors )
return render_to_response('places/contact_form.html', {'form': form})
以上是我在学习Manipulator时一些个人理解，暂时记录如此，以后我会更深入的了解他们，同时非常感谢limodou的解惑，他真是个热心人，向他学习！
from django import formsurgency_choices = ( (1, "Extremely urgent"), (2, "Urgent"), (3, "Normal"), (4, "Unimportant"),)class ContactManipulator(forms.Manipulator): def __init__(self): self.fields = ( forms.EmailField(field_name="from", is_required=True), forms.TextField(field_name="subject", length=30, maxlength=200, is_required=True), forms.SelectField(field_name="urgency", choices=urgency_choices), forms.LargeTextField(field_name="contents", is_required=True), ) def save(self): #.而且我们还可以定义带有初始化参数的custom Manipulator
如：
class ContactManipulator(forms.Manipulator): def __init__(self,object_id=None): self.object_id = object_id self.fields = ( forms.EmailField(field_name="fromEmail", is_required=True), forms.TextField(field_name="subject", length=30, maxlength=200, is_required=True), forms.SelectField(field_name="urgency", choices=urgency_choices), forms.LargeTextField(field_name="contents", is_required=True), ) def save(self, new_data): fromemail = new_data["fromEmail"] subject = new_data["subject"] urgency = new_data["urgency"] contents = new_data["contents"] if self.object_id: obj = Contact.objects.get(pk=int(self.object_id)) obj.fromEmail = fromemail obj.subject = subject obj.urgency = urgency; obj.contents = contents; else: obj = Contact(fromEmail=fromemail, subject=subject, urgency=urgency,contents=contents) obj.save()那这个ContactManipulator应该怎么用呢
#创建 def contact_form(request): manipulator = ContactManipulator() if request.POST: new_data = request.POST.copy() errors = manipulator.get_validation_errors(new_data) if not errors: manipulator.do_html2python(new_data) manipulator.save(new_data) return HttpResponseRedirect("/formapp/contact/") else: errors = new_data = {} form = forms.FormWrapper(manipulator, new_data, errors) return render_to_response('places/contact_form.html', {'form': form})#修改def editcontact(request,contactid): manipulator = ContactManipulator(contactid) if request.POST: new_data = request.POST.copy() errors = manipulator.get_validation_errors(new_data) if not errors: manipulator.do_html2python(new_data) manipulator.save(new_data) # Do a post-after-redirect so that reload works, etc. return HttpResponseRedirect("/formapp/contact/1") else: errors = {} contact = Contact.objects.get(id = contactid) new_data = contact.__dict__ form = forms.FormWrapper(manipulator, new_data,errors ) return render_to_response('places/contact_form.html', {'form': form}) 以上是我在学习Manipulator时一些个人理解，暂时记录如此，以后我会更深入的了解他们，同时非常感谢limodou的解惑，他真是个热心人，向他学习！