与 Django Filter field name greater than 相关的主要问题是它不适用于某些类型的数据。 例如，如果您有一个名为“name”的字符串字段，并且您尝试使用值为“大于”的 Filter 字段，Django 将不允许。
I am using the Django-filter package and I have a field name that is greater than. How do I write this in the filter class?
<code>class MyFilter(django_filters.FilterSet):
field_name = django_filters.NumberFilter(field_name='field_name', lookup_expr='gt')
class Meta:
model = MyModel
fields = ['field_name']
</code>
A:
You can use <code>__gt</code> (greater than) as a lookup expression for <code>NumberFilter</code>. You also need to specify the <code>lookup_expr</code>, otherwise it defaults to <code>exact</code>. For example, if you wanted to filter by all objects with a field named "foo" that was greater than 5, you could do something like this:
<blockquote>
<p><strong><em>(Note: This is untested code, but should give you an idea of how to use it.)</em></strong></p>
</blockquote>
<code>class MyFilter(django_filters.FilterSet):
foo = django_filters.NumberFilter(field_name='foo', lookup_expr='gt')
class Meta: # noqa D106 missing docstring in public module D205 1 blank line required between summary line and description D400 first line should end with a period (not '...') D401 first line should be in imperative mood; try rephrasing D402 No blank lines allowed after function docstring D403 Blank line required before last section level tag (e.g. 'return') D404 Section name should end with a newline (not '...n') PEP8 E501 line too long (82 > 79 characters) W504 line break after binary operator W605 invalid escape sequence U W606 '' followed by non-ASCII character PEP8 E265 block comment should start with '# ' PEP8 E266 too many leading '#' for block comment PEP8 E301 expected 1 blank line, found 0 PEP8 E302 expected 2 blank lines, found 0 PEP8 E303 too many blank lines (3) pep8 N802 function name should be lowercase pep8 N803 argument name should be lowercase pep8 N806 variable in function should be lowercase pep8 N815 docstring should have verb at beginning pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pylint C0111 missing module docstring C0301 Line too long C0326 Bad spacing around keyword / parameter equals C0412 import only modules... W0221 Arguments number differs from overridden method W0511 TODO & FIXME not identified as such C0413 import at top of file C0414 import as member ...C0415 import order not recognized ...C0305 relative import contains dots ...E1120 no value passed for parameter `model` ...E1121 unexpected keyword argument `fields` ...E1122 unexpected keyword argument `fields` ...E1123 unexpected keyword argument `fields` ...E1124 unexpected keyword argument `fields` ...W0613 Unused arguments [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'throwaway1','throwaway2','throwaway3','throwaway4','throwaway5','throwaway6','throwaway7','throwaway9','throwaway10',' throwaway11,' throwawy12,' throwawy13,' throwawy14,' throwawy15,' throwawy16] R1705 Consider using enumerate instead of iterating over a list R1710 Consider using set comprehension instead of set construction via looping over a list R1720 Consider using zip instead of iterating over lists in parallel R1721 Consider using join() instead of concatenating strings manually R1722 Consider using join() instead of concatenating strings manually R1723 Don't use sum() on an empty sequence R1724 Don't check types when using isinstance(). Use issubclass() instead.</p>
foo = django_filters.<b><i>"Greater Than" Lookup Expression Here!</i></b>(field__foo=5)</p></blockquote> If you want more information on lookups and filtersets see the docs here https://django-filter.readthedocs.io/en/master/guide/usage.html#basic-usage . If you want more information on lookups see here https://docs.djangoproject.com/en/dev/ref/models/querysets/#field-lookups . Good luck! Let me know if this helps! Cheers! -JLKDGJLKDGJLKDGJLKDGJLKDGJLKDGJLDKFGLDKFGJDFLDKFGJDFLDKFGJDFLDKFGJDFLDKFGJDFLDKFGLDFGLDFGLDFGLDFGLDFGDFLGDFLGDFLGDFLGFDLGFDLGFDLGFDLGFDLGFDLFDLGFDLGFDLGFDLGFDLGFDLDLGDDDDDDDDDDDDDDDDDDDD DDDSSSSSSSSSSSSFFFFFFFFFFFFFFFGGGGGGGGGGGGGGHHHHHHHHHHHHHHHJJJJJJJJJJJJKKKKKKKKKKLLLLLLMMMMMMNNNNOOOPPPQQQRRRSTTTUUUVVVWWXXYYZZ[[[\\]]^___^^^````aabbccddeeffgghhiijjkkllmmnnooppqqrrssvvwwxxyyzz{{{|||}}}~~~¡¢£¤¥¦¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½ÀÁÂÃÄÅÆÇÈÉÊËÍÎÍ×ÛÛ×Û×Û×Û×Û×ÛÛÛÛÛÛÛÛ²²²²²²²îïîïîïîïîïîïîïîïíñíñíñíñíñíñóôóôóôóôóôöøöøöøöøöøúûúûúûúûúûü þü þü þü þü þü þü þü þ ý ý ý ý ý ý àáâãäåæçèéêëðèéêëðèéêëðèéêëðèéêëðè éêëðè éêëðè éêëðè éêëðè éêëðè éêëðè éáâãäåæçåæçåæçåæçåæçåæçåæçàáâãäàáâãäàáâãäàáâãäàáâãäàáâãä àáâãä àáâãä àáâãä àáâãä àáâãä à^a^a^a^a^a^^aa^^aa^^aa^^aa^^aaaaaaaaaaaaaaaaaaa^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^bbbbbbbbbbbbbbbcccccccdddddddeeeeeeeefffffffggggggghhhhhhhiiiiiiiijjjjjjjkkkkkkklllllllmmmmmmmnnnnnnoooooooppppppqqqqrrrrrsssssstttuuuuuuuvvvvvvwwwwwwwxxxxxxxxyy
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使用过滤器和字段的提示
在 Django 中使用过滤器和字段时，需要牢记以下几点：
1. 始终尽可能使用最具体的过滤器或字段。 这将使您的代码更具可读性，并且不太可能导致错误。
2. 在代码中的多个地方使用相同的过滤器或字段名称以避免混淆。
3. 尽可能为输入和输出使用相同的字段名称，这样您就可以轻松比较不同请求之间的结果。
