如何擴展 Django 表單 class？

Question

我想基於這個創建多個類似的 forms：

class DatabaseForm(forms.Form):
    
    label = "Database label"  # This does not work, but I also can't define it in __init__ method, as I can't access self below in "name" field

    name = forms.BooleanField(label=label, required=False)
    username = forms.CharField(label="Username", required=False)
    password = forms.CharField(label="Password", required=False)

我只更改label，如下所示：

class MySQLForm(DatabaseForm):
    label = "MySQL"  # Somehow override label of super class

我怎樣才能做到這一點？

Answer 1

您可以在__init__構造函數中覆蓋 label：

class MySQLForm(DatabaseForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['name'].label = 'MySQL'

您還可以在DatabaseForm中使用參數：

class DatabaseForm(forms.Form):
    name_label = 'Database label'
    name = forms.BooleanField(label=None, required=False)
    username = forms.CharField(label='Username', required=False)
    password = forms.CharField(label='Password', required=False)
    
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['name'].label = self.name_label

class MySQLForm(DatabaseForm):
    name_label = 'MySQL'

Answer 2

您可以在__init__中設置字段 label 並通過self.label訪問 class 屬性

class DatabaseForm(forms.Form):

    label = "Database label"

    name = forms.BooleanField(required=False)
    username = forms.CharField(label="Username", required=False)
    password = forms.CharField(label="Password", required=False)

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['name'].label = self.label


class MySQLForm(DatabaseForm):
    label = "MySQL"