Python 如何使用 FormFields 的 WTForms FieldList？
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How to use a WTForms FieldList of FormFields?
提问by kramer65
I'm building a website using Flaskin which I use WTForms. In a Form I now want to use a FieldList of FormFields as follows:
我正在使用Flask构建一个网站，其中使用WTForms。在表单中，我现在想使用 FormFields 的 FieldList，如下所示：
class LocationForm(Form):
location_id = StringField('location_id')
city = StringField('city')
class CompanyForm(Form):
company_name = StringField('company_name')
locations = FieldList(FormField(LocationForm))
so to give people the ability to enter a company with two locations (dynamic adding of locations comes later) I do this on the front side:
因此，为了让人们能够进入具有两个位置的公司（稍后会动态添加位置），我在前端执行此操作：
<form action="" method="post" role="form">
{{ companyForm.hidden_tag() }}
{{ companyForm.company_name() }}
{{ locationForm.location_id() }}
{{ locationForm.city() }}
{{ locationForm.location_id() }}
{{ locationForm.city() }}
<input type="submit" value="Submit!" />
</form>
So on submit I print the locations:
所以在提交时我打印位置：
print companyForm.locations.data
but I get
但我明白了
[{'location_id': u'', 'city': u''}]
I can print the values of the first location using the locationForm (see below), but I still don't know how to get the data of the second location.
我可以使用 locationForm 打印第一个位置的值（见下文），但我仍然不知道如何获取第二个位置的数据。
print locationForm.location_id.data
print locationForm.city.data
So the list of locations does have one dict with empty values, but:
所以位置列表确实有一个空值的字典，但是：
- Why does the list of locations have only one, and not two dicts?
- And why are the values in the location dict empty?
- 为什么位置列表只有一个，而不是两个字典？
- 为什么 location dict 中的值是空的？
Does anybody know what I'm doing wrong here? All tips are welcome!
有谁知道我在这里做错了什么？欢迎所有提示！
采纳答案by Jaime Gómez
For starters, there's an argument for the FieldListcalled min_entries, that will make space for your data:
首先，有一个FieldList的参数叫做min_entries，它将为您的数据腾出空间：
class CompanyForm(Form):
company_name = StringField('company_name')
locations = FieldList(FormField(LocationForm), min_entries=2)
This will setup the list the way you need. Next you should render the fields directly from the locationsproperty, so names are generated correctly:
这将按照您需要的方式设置列表。接下来，您应该直接从locations属性呈现字段，以便正确生成名称：
<form action="" method="post" role="form">
{{ companyForm.hidden_tag() }}
{{ companyForm.company_name() }}
{{ companyForm.locations() }}
<input type="submit" value="Submit!" />
</form>
Look at the rendered html, the inputs should have names like locations-0-city, this way WTForms will know which is which.
查看渲染的 html，输入的名称应该类似于locations-0-city，这样 WTForms 就会知道哪个是哪个。
Alternatively, for custom rendering of elements do
或者，对于元素的自定义呈现
{% for l in companyForms.locations %}
{{ l.form.city }}
{% endfor %}
(in wtforms alone l.cityis shorthand for l.form.city. However, that syntax seems to clash with Jinja, and there it is necessary to use the explicit l.form.cityin the template.)
（仅在 wtforms 中l.city是 的简写l.form.city。但是，该语法似乎与 Jinja 冲突，因此有必要l.form.city在模板中使用显式。）
Now to ready the submitted data, just create the CompanyFormand iterate over the locations:
现在准备提交的数据，只需创建CompanyForm并迭代位置：
for entry in form.locations.entries:
print entry.data['location_id']
print entry.data['city']
