Question

我正在尝试从SQLAlchemy数据库中动态创建WTForm SelectField条目，如here所示，但似乎每个选择元组的第一部分都应该repr()或str()是User对象。我刚刚发现了QuerySelectField但wtforms.ext.*个软件包已被弃用。

class ChangeAccountForm(FlaskForm):
    def __init__(self, *args, **kwargs):
        # Queries user database and sets user choices
        super(ChangeAccountForm, self).__init__(*args, **kwargs)
        self.user.choices = [(i, i.username) for i in User.query.all()]

    user = SelectField('Gebruiker', validators=[Optional()])

Answer 1

来自wtforms docs：

class wtforms.fields.SelectField(default field arguments, choices=[], 
    coerce=unicode, option_widget=None)

"""        
Select fields keep a choices property which is a sequence of (value, 
label) pairs. The value portion can be any type in theory, but as form 
data is sent by the browser as strings, you will need to provide a 
function which can coerce the string representation back to a 
comparable object.
"""

因此，如果在没有正确修改 repr 字符串的情况下更新用户模型，那么使用user.id的传统方法是一种更加面向未来的方法，可以将正确的对象强制保留回用户。＃39; ID＆＃39;将始终作为主键提供。

WTForms将选择变成字符串

1 个答案: