使用flask-wtf和sqlalchemy生成动态表单 [英] Generate a dynamic form using flask-wtf and sqlalchemy
问题描述
我有一个 web 应用程序,它允许用户创建自己的字段,以便稍后在表单中呈现.
我有一个像这样的模型 Formfield:
class Formfield(db.Model):id = db.Column(db.Integer, primary_key = True)form_id = db.Column(db.Integer, db.ForeignKey('formbooking.id'))标签 = db.Column(db.String(80))placeholder_text = db.Column(db.String(80))help_text = db.Column(db.String(500))box_checked = db.Column(db.Boolean, nullable = True, default = False)options = db.Column(db.String) # JSON 放在这里?答案 = db.Column(db.String)required = db.Column(db.Boolean, nullable = False, default = False)订单 = db.Column(db.Integer)字段类型 = db.Column(db.Integer)
我用来表示一个字段,不管是什么类型的(复选框、输入、未来更多).
如您所见,每个字段都有一个到 form_id 的 FK.
我正在尝试为给定的 form_id 生成动态表单.问题是我需要确定要为每个 Formfield 呈现的字段类型.所以我还需要在某个时候处理 fieldtype.
我想一个解决方案是以某种方式将 form_id 传递给我的 Form 类中的一个函数.
我不知道该怎么做或在哪里寻找解决方案.
任何帮助将不胜感激!
我想我设法用这里的想法创建了动态表单 https://groups.google.com/forum/#!topic/wtforms/cJl3aqzZieA
你必须在视图函数中创建一个动态表单,获取你想要获取的表单字段,并迭代每个字段来构造这个表单对象.我用于字段类型的简单文本而不是整数值.因为它在代码级别看起来很容易阅读.
class FormView(MethodView):定义获取(自我):类 DynamicForm(wtforms.Form):通过dform = main.models.Form.objects.get(name="name2")名称 = dform.name对于 dform.fields 中的 f:打印 f.labelsetattr(DynamicForm, f.label, self.getField(f))d = DynamicForm() # 在渲染之前不要忘记实例化你的新表单对于 d 中的字段:打印字段#可以看到字段的html输出return render_template("customform.html", form=d)def getField(self, field):如果 field.fieldtype == "text":返回 TextField(field.label)如果 field.fieldtype == 密码":返回 PasswordField(field.label)# 可以在每个新的字段类型上扩展 if 子句
对于一个简单的表单渲染 jinja 模板 'forms.html'
{% 宏渲染(form) -%}<字段集>{% 用于表单 %} 中的字段{% if field.type in ['CSRFTokenField', 'HiddenField'] %}{{ 场地() }}{% 别的 %}<div class="form-group {% if field.errors %}error{% endif %}">{{ field.label }}<div class="输入">{% if field.name == "body" %}{{ 字段(行 = 10,列 = 40)}}{% 别的 %}{{ 场地() }}{% 万一 %}{% if field.errors 或 field.help_text %}<span class="help-inline">{% if field.errors %}{{ field.errors|join(' ') }}{% 别的 %}{{ field.help_text }}{% 万一 %}</span>{% 万一 %}
{% 万一 %}{% 结束为 %}</fieldset>{% 宏 %}
而customform.html是这样的
{% 扩展 "base.html" %}{% import "forms.html" as forms %}{% 块内容 %}{{ forms.render(form) }}{% 结束块 %}
I have a webapp that allows users to create their own fields to be rendered in a form later on.
I have a model Formfield like so:
class Formfield(db.Model):
id = db.Column(db.Integer, primary_key = True)
form_id = db.Column(db.Integer, db.ForeignKey('formbooking.id'))
label = db.Column(db.String(80))
placeholder_text = db.Column(db.String(80))
help_text = db.Column(db.String(500))
box_checked = db.Column(db.Boolean, nullable = True, default = False)
options = db.Column(db.String) # JSON goes here?
answer = db.Column(db.String)
required = db.Column(db.Boolean, nullable = False, default = False)
order = db.Column(db.Integer)
fieldtype = db.Column(db.Integer)
that I use to represent a field, whatever the kind (checkbox, input, more in the future).
As you can see, every field has a FK to a form_id.
I’m trying to generate a dynamic form for a given form_id. The catch is that I need to determine the type of field to render for every Formfield. So I also need to process the fieldtype at some point.
I guess a solution would be to somehow pass the form_id to a function in my Form class.
I have no clue how to do it or where to look for a solution.
Any help would be very appreciated!
I think I managed to create dynamic forms with the idea from here https://groups.google.com/forum/#!topic/wtforms/cJl3aqzZieA
you have to create a dynamic form at view function, fetch the form field you want to get, and iterate every field to construct this form object. I used for fieldtypes simple text instead of integer values. Since it seems easy to read at code level.
class FormView(MethodView):
def get(self):
class DynamicForm(wtforms.Form): pass
dform = main.models.Form.objects.get(name="name2")
name = dform.name
for f in dform.fields:
print f.label
setattr(DynamicForm , f.label, self.getField(f))
d = DynamicForm() # Dont forget to instantiate your new form before rendering
for field in d:
print field # you can see html output of fields
return render_template("customform.html", form=d)
def getField(self, field):
if field.fieldtype == "text":
return TextField(field.label)
if field.fieldtype == "password":
return PasswordField(field.label)
# can extend if clauses at every new fieldtype
for a simple form render jinja template 'forms.html'
{% macro render(form) -%}
<fieldset>
{% for field in form %}
{% if field.type in ['CSRFTokenField', 'HiddenField'] %}
{{ field() }}
{% else %}
<div class="form-group {% if field.errors %}error{% endif %}">
{{ field.label }}
<div class="input">
{% if field.name == "body" %}
{{ field(rows=10, cols=40) }}
{% else %}
{{ field() }}
{% endif %}
{% if field.errors or field.help_text %}
<span class="help-inline">
{% if field.errors %}
{{ field.errors|join(' ') }}
{% else %}
{{ field.help_text }}
{% endif %}
</span>
{% endif %}
</div>
</div>
{% endif %}
{% endfor %}
</fieldset>
{% endmacro %}
and customform.html is like this
{% extends "base.html" %}
{% import "forms.html" as forms %}
{% block content %}
{{ forms.render(form) }}
{% endblock %}
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