Basic HTTP forms posting

I have a page with nothing on it but this form:

<form method="post" action="/sign-in">
    <input type="text" id="username" />
    <input type="password" id="password" />
    <input type="submit" />
</form>

After entering values into "usernamed" and "password", when the form is submitted via the submit butt开发者_如何学Con, I get this HTTP header:

POST http://localhost:12339/sign-in HTTP/1.1
Host: localhost:12339
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.12)...
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Connection: keep-alive
Referer: http://localhost:12339/
Cookie: Authorization=test
Content-Type: application/x-www-form-urlencoded
Content-Length: 0

My question is, why aren't the "username" and "password" form field values being posted in the content of the HTTP post?

---

When sending form data, the names are retrieved from the name attribute, not from the id. Try this:

<form method="post" action="/sign-in">
    <input type="text" name="username" />
    <input type="password" name="password" />
    <input type="submit" />
</form>

Or, if you need the id for something else:

<form method="post" action="/sign-in">
    <input type="text" id="username" name="username" />
    <input type="password" id="password" name="password" />
    <input type="submit" />
</form>