django自定义Field实现一个字段存储以逗号分隔的字符串

实现了在一个字段存储以逗号分隔的字符串，返回一个相应的列表

from django import forms
from django.db import models
from django.utils.text import capfirst
from django.core import exceptions


class MultiSelectFormField(forms.MultipleChoiceField):
 widget = forms.CheckboxSelectMultiple
 def __init__(self, *args, **kwargs):
 self.max_choices = kwargs.pop('max_choices', 0)
 super(MultiSelectFormField, self).__init__(*args, **kwargs)
 def clean(self, value):
 if not value and self.required:
 raise forms.ValidationError(self.error_messages['required'])
 # if value and self.max_choices and len(value) > self.max_choices:
 # raise forms.ValidationError('You must select a maximum of %s choice%s.'
 # % (apnumber(self.max_choices), pluralize(self.max_choices)))
 return value

class MultiSelectField(models.Field):
 __metaclass__ = models.SubfieldBase
 def get_internal_type(self):
 return "CharField"
 def get_choices_default(self):
 return self.get_choices(include_blank=False)
 def _get_FIELD_display(self, field):
 value = getattr(self, field.attname)
 choicedict = dict(field.choices)
 def formfield(self, **kwargs):
 # don't call super, as that overrides default widget if it has choices
 defaults = {'required': not self.blank, 'label': capfirst(self.verbose_name),
 'help_text': self.help_text, 'choices': self.choices}
 if self.has_default():
 defaults['initial'] = self.get_default()
 defaults.update(kwargs)
 return MultiSelectFormField(**defaults)
 def get_prep_value(self, value):
 return value
 def get_db_prep_value(self, value, connection=None, prepared=False):
 if isinstance(value, basestring):
 return value
 elif isinstance(value, list):
 return ",".join(value)
 def to_python(self, value):
 if value is not None:
 return value if isinstance(value, list) else value.split(',')
 return ''
 def contribute_to_class(self, cls, name):
 super(MultiSelectField, self).contribute_to_class(cls, name)
 if self.choices:
 func = lambda self, fieldname = name, choicedict = dict(self.choices): ",".join([choicedict.get(value, value) for value in getattr(self, fieldname)])
 setattr(cls, 'get_%s_display' % self.name, func)
 def validate(self, value, model_instance):
 arr_choices = self.get_choices_selected(self.get_choices_default())
 for opt_select in value:
 if (int(opt_select) not in arr_choices): # the int() here is for comparing with integer choices
 raise exceptions.ValidationError(self.error_messages['invalid_choice'] % value)
 return
 def get_choices_selected(self, arr_choices=''):
 if not arr_choices:
 return False
 list = []
 for choice_selected in arr_choices:
 list.append(choice_selected[0])
 return list
 def value_to_string(self, obj):
 value = self._get_val_from_obj(obj)
 return self.get_db_prep_value(value)

以上就是django自定义Field实现一个字段存储以逗号分隔的字符串。只有正直、忠诚、宽容和拥有仁爱之心的人才能够达到真正意义上的成功。不具备这些品质的人，就无法体会到成功的滋味，因为成功和幸福一样，不在于外在的富有，而在于内心的感受。更多关于django自定义Field实现一个字段存储以逗号分隔的字符串请关注haodaima.com其它相关文章！