在 Django 模型表单中使用模型属性

•浏览 1

Use Model Property in a Django Model Form

我正在尝试在模型表单中使用模型属性，例如字段，但到目前为止还没有任何运气。结果是表单只呈现模型字段，而不是我定义的属性。知道如何让表单识别添加到模型中的属性吗？我希望看到纬度属性作为表单中的另一个字段添加。

模型.py:

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...

Forms.py:

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...

若干年后。一个完整的答案，在 Django 中工作到 2.2。正如其他人指出的那样，模型表单中只包含真正的数据库字段。因此，您需要：

  • 定义自定义模型表单，添加您的 @property 字段
  • 排除您的几何字段
  • 在表单的 __init__ 中，获取值，并将其设置为 initial。
  • 自定义您的保存方法(在表单或管理员上)

注意：这也适用于更复杂的情况，您想抽象出一些更复杂的数据库结构...

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...

ModelForm 仅自动生成 Django 字段。

  • 您需要在 ModelForm 中定义您的字段
  • 可能使几何场隐藏
  • 编写自定义 ModelForm Save 方法，分别保存模型字段和模型属性。
  • 修改视图以设置 ModelForm 的初始值

例如这样的：

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...

在你看来

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...

您的属性不是 Field 实例，因此 ModelForm 无法自动为其生成表单字段。您需要在 InventoryPlotForm 上显式定义一个 latitude 字段，并在表单的 __init__ 和 save 方法中管理其检索和更新。或者，您可以实现自己的 Widget 类并告诉您的 InventoryPlotForm 将其用于 geometry 字段：

class Plot(models.Model):

    plot_id = models.AutoField(primary_key=True)

    plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)

    geometry = models.PointField(srid=2163, null=True, blank=True) 

    objects = models.GeoManager()



    @property

    def latitude(self):

      self.geometry.transform(4326)

      return self.geometry.y



    @latitude.setter

    def latitude(self, latitude):

      self.geometry.y = latitude
class InventoryPlotForm(ModelForm):

  class Meta:

    model = ForestInventoryPlot

    exclude = {"geometry"}

class InventoryPlotForm(ModelForm):



  class Meta:

    model = ForestInventoryPlot

    exclude = ("geometry", )



  latitude = forms.WhateverField()



  def __init__(self, *args, **kwargs):

    instance = kwargs.get('instance', None)

    if instance:

      kwargs['initial'] = {'latitude': instance.latitude, }

    super().__init__(*args, **kwargs)



  def save(self, *args, **kwargs):

    self.instance.latitude = self.cleaned_data['latitude']

    return super().save(*args, **kwargs)

class InventoryPlotForm(ModelForm):

  latitude = forms.CharField(max_length=52)      # Something like this



  def save(self, commit=True):

    model_instance = super(InventoryPlotForm, self).save(commit=False)

    result = super(InventoryPlotForm, self).save(commit=True)

    model_instance.latitude = self.cleaned_data['latitude']

    model_instance.save()

    return result



  class Meta:

    model = ForestInventoryPlot

    widgets = {'geometry': HiddenInput()}
...

form = InventoryPlotForm(instance=forestinventoryplot,

            initial={"latitude":forestinventoryplot.latitude})

...
class InventoryPlotForm(ModelForm):

  class Meta(object):

    widgets = {

      'geometry': MyGeometryWidget,

    }

    ...

  ...
赞 (0)
« 上一篇
下一篇 »

相关推荐

  • Spring部署设置openshift

    Springdeploymentsettingsopenshift我有一个问题让我抓狂了三天。我根据OpenShift帐户上的教程部署了spring-eap6-quickstart代码。我已配置调试选项，并且已将Eclipse工作区与OpehShift服务器同步-服务器上的一切工作正常，但在Eclipse中出现无法消除的错误。我有这个错误：cvc-complex-type.2.4.a:Invali…
    2025-04-161

  • 检查Java中正则表达式中模式的第n次出现

    CheckfornthoccurrenceofpatterninregularexpressioninJava本问题已经有最佳答案，请猛点这里访问。我想使用Java正则表达式检查输入字符串中特定模式的第n次出现。你能建议怎么做吗？这应该可以工作：MatchResultfindNthOccurance(intn,Patternp,CharSequencesrc){Matcherm=p.matcher…
    2025-04-161

  • 如何让 JTable 停留在已编辑的单元格上

    HowtohaveJTablestayingontheeditedcell如果有人编辑JTable的单元格内容并按Enter，则内容会被修改并且表格选择会移动到下一行。是否可以禁止JTable在单元格编辑后转到下一行？原因是我的程序使用ListSelectionListener在单元格选择上同步了其他一些小部件，并且我不想在编辑当前单元格后选择下一行。Enter的默认绑定是名为selectNext…
    2025-04-161

  • Weblogic 12c 部署

    Weblogic12cdeploy我正在尝试将我的应用程序从Tomcat迁移到Weblogic12.2.1.3.0。我能够毫无错误地部署应用程序，但我遇到了与持久性提供程序相关的运行时错误。这是堆栈跟踪：javax.validation.ValidationException:CalltoTraversableResolver.isReachable()threwanexceptionatorg.…
    2025-04-161

  • Resteasy Content-Type 默认值

    ResteasyContent-Typedefaults我正在使用Resteasy编写一个可以返回JSON和XML的应用程序，但可以选择默认为XML。这是我的方法：@GET@Path("/content")@Produces({MediaType.APPLICATION_XML,MediaType.APPLICATION_JSON})publicStringcontentListRequestXm…
    2025-04-161

  • 代码不会停止运行，在 Java 中

    thecodedoesn'tstoprunning,inJava我正在用Java解决项目Euler中的问题10，即"Thesumoftheprimesbelow10is2+3+5+7=17.Findthesumofalltheprimesbelowtwomillion."我的代码是packageprojecteuler_1;importjava.math.BigInteger;importjava…
    2025-04-161

  • Out of memory java heap space

    Outofmemoryjavaheapspace我正在尝试将大量文件从服务器发送到多个客户端。当我尝试发送大小为700mb的文件时，它显示了"OutOfMemoryjavaheapspace"错误。我正在使用Netbeans7.1.2版本。我还在属性中尝试了VMoption。但仍然发生同样的错误。我认为阅读整个文件存在一些问题。下面的代码最多可用于300mb。请给我一些建议。提前致谢publicc…
    2025-04-161

  • Log4j 记录到共享日志文件

    Log4jLoggingtoaSharedLogFile有没有办法将log4j日志记录事件写入也被其他应用程序写入的日志文件。其他应用程序可以是非Java应用程序。有什么缺点？锁定问题？格式化？Log4j有一个SocketAppender，它将向服务发送事件，您可以自己实现或使用与Log4j捆绑的简单实现。它还支持syslogd和Windows事件日志，这对于尝试将日志输出与来自非Java应用程序…
    2025-04-161
手机版技术脚本