widgets.py 文件源码

def value_from_datadict(self, data, files, name):
        file_value = super(widgets.ClearableFileInput, self) \
            .value_from_datadict(data, files, name)
        checkbox_value = widgets.CheckboxInput() \
            .value_from_datadict(data, files, self.clear_checkbox_name(name))
        if not self.is_required and checkbox_value:
            return False
        return file_value