python - 如何用 3 个选择渲染 DateField

Question

我正在寻找最简单、最干净的方法来呈现具有 3 个选择的基本 DateField。

<select>day</select><select>month</select><select>year</select>

(如果可能，使用“格式”来选择如何显示最终渲染)

Answer 1

您可以利用 DateField 将处理多值输入并用空格将它们连接在一起这一事实，这样您就可以避免使用次要形式，而只是提供一系列输入:

from wtforms.widgets.core import Select, HTMLString, html_params

class SelectDateWidget(object):
    FORMAT_CHOICES = {
        '%d': [(x, str(x)) for x in range(1, 32)],
        '%m': [(x, str(x)) for x in range(1, 13)],
        '%y': [(x, str(x)) for x in range(1950, 2014)],
    }

    def __call__(self, field, **kwargs):
        field_id = kwargs.pop('id', field.id)
        html = []
        for format in field.format.split():
            choices = self.FORMAT_CHOICES[format]
            id_suffix = format.replace('%', '-')
            params = dict(kwargs, name=field.name, id=field_id + id_suffix)
            html.append('<select %s>' % html_params(params))
            if field.data:
                current_value = int(field.data.strftime(format))
            else:
                current_value = None
            for value, label in choices:
                selected = (value == current_value)
                html.append(Select.render_option(value, label, selected))
            html.append('</select>')

        return HTMLString(''.join(html))


# Usage
class MyForm(Form):
    american_date = DateField(format='%m %d %y', widget=SelectDateWidget())
    european_date = DateField(format='%d %m %y', widget=SelectDateWidget())