在Django中如何不创建表单使管理员字段为非必填？

Question

每次我在Django的管理后台添加一个新玩家时，都会出现一个错误提示，内容是“这个字段是必填的。”

有没有办法让某个字段变成非必填的，而不需要创建一个自定义表单？我可以在models.py或admin.py里做到这一点吗？

这是我在models.py里定义的类的样子。

class PlayerStat(models.Model):
    player = models.ForeignKey(Player)

    rushing_attempts = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Attempts"
        )
    rushing_yards = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Yards"
        )
    rushing_touchdowns = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Touchdowns"
        )
    passing_attempts = models.CharField(
        max_length = 100,
        verbose_name = "Passing Attempts"
        )

谢谢！

Answer 1

如果在模型层设置了某个字段可以留空，这实际上意味着可以使用空字符串。空字符串和空值（null）其实是两回事。不要因为框架设置了一些不好的默认选项而破坏你的数据完整性。

与其直接设置为空，不如重写 get_form 方法：

    def get_form(self, request, obj=None, **kwargs):
        form = super().get_form(request, obj, **kwargs)
        form.base_fields["rushing_attempts"].required = False

Answer 2

使用 blank=True 和 null=True

class PlayerStat(models.Model):
    player = models.ForeignKey(Player)

    rushing_attempts = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Attempts",
        blank=True,
        null=True
        )
    rushing_yards = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Yards",
        blank=True,
        null=True
        )
    rushing_touchdowns = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Touchdowns",
        blank=True,
        null=True
        )
    passing_attempts = models.CharField(
        max_length = 100,
        verbose_name = "Passing Attempts",
        blank=True,
        null=True
        )

Answer 3

只需在你的模型中放入

blank=True

也就是说：

rushing_attempts = models.CharField(
        max_length = 100,
        verbose_name = "Rushing Attempts",
        blank=True
        )