我正在使用以下 iframe json 代码在我的网站上显示一个用于用户注册的表单。虽然当我在一定数量之后添加自定义字段时，我收到一条错误消息：
错误请求 您的浏览器发送了此服务器无法理解的请求。请求头字段的大小超过服务器限制。推荐人/n
我尝试联系我的托管帮助，他们说 facebook 代码存在问题，但我想这不是问题所在，因为在一定数量的复选框中代码可以正常工作，但一旦超出此范围，我就会明白上述错误。这是代码：
<iframe src='http://www.facebook.com/plugins/registration.php?
client_id=325340244194060&
redirect_uri=http://www.pingcampus.com/facebook_registration_plugin/fbwe/trial.php&
fields=[
{
"name": "name"
},
{
"name": "email"
},
{
"name": "gender"
},
{
"name": "birthday"
},
{
"name": "Arts",
"description": "Arts",
"type": "checkbox",
"value": "Arts"
},
{
"name": "Act",
"description": "Act",
"type": "checkbox",
"value": "Act"
},
{
"name": "Cooking",
"description": "Cooking",
"type": "checkbox",
"value": "Cooking"
},
{
"name": "Dance",
"description": "Dance",
"type": "checkbox",
"value": "Dance"
},
{
"name": "Designing",
"description": "Designing",
"type": "checkbox",
"value": "Designing"
},
{
"name": "Fashion",
"description": "Fashion Designing",
"type": "checkbox",
"value": "Fashion Designing"
},
{
"name": "Interior",
"description": "Interior Designing",
"type": "checkbox",
"value": "Interior Designing"
},
{
"name": "Modeling",
"description": "Modeling",
"type": "checkbox",
"value": "Modeling"
},
{
"name": "Photography",
"description": "Photography",
"type": "checkbox",
"value": "Photography"
},
{
"name": "Poetry",
"description": "Poetry / Writing",
"type": "checkbox",
"value": "Poetry / Writing"
},
{
"name": "Programming",
"description": "Programming",
"type": "checkbox",
"value": "Programming"
},
{
"name": "Reading",
"description": "Reading",
"type": "checkbox",
"value": "Reading"
},
{
"name": "Sketching",
"description": "Sketching / Drawing",
"type": "checkbox",
"value": "Sketching / Drawing"
},
{
"name": "Singing",
"description": "Singing",
"type": "checkbox",
"value": "Singing"
},
{
"name": "Sports",
"description": "Sports",
"type": "checkbox",
"value": "Sports"
},
{
"name": "Stunting",
"description": "Stunting",
"type": "checkbox",
"value": "Stunting"
},
{
"name": "Videography",
"description": "Videography",
"type": "checkbox",
"value": "Videography"
},
{
"name": "Other",
"description": "Other",
"type": "checkbox",
"value": "Other"
},
{
"name": "captcha"
}
]'
scrolling="auto"
frameborder="no"
style="border:none"
allowTransparency="true"
width="500"
height="800"
>
</iframe>
谁能猜出我哪里出错了？我正在使用此处给出的示例代码通过 php 处理表单。如果需要请询问代码，我也会提供 php 代码，但它与上面链接中的示例几乎相同