处理html下拉表单

I have the following html drop down form:

<form method='post' action='signup.php'>$error

<span class='fieldname'>Sex</span>
<select name ="sex">
  <option value="female">Female</option>
  <option value="male">Male</option>
</select> <br />

_END;

But when I process the form in php I get a blank (no value) for $sex:

$sex = $_POST['sex'];
echo $sex;

Give us more script.Perhaps some error.I used the below code and it worked fine.

<?php
if(isset($_POST['sex']))
{
$sex = $_POST['sex'];
echo 'Result: '.$sex;
}
?>
<form method='post' action=''>
<span class='fieldname'>Sex</span>
<select name ="sex">
  <option value="female">Female</option>
  <option value="male">Male</option>
</select><input type="submit"> <br />
</form>

option value so you must use selected="selected" any one. and try following code.

<form method='post' action=''>
<span class='fieldname'>Sex</span>
<select name ="sex">
  <option value="female" selected="selected">Female</option>
  <option value="male">Male</option>
</select><input type="submit"> <br />
</form>

<?php
       $sex = isset($_POST['sex']) ? mysql_real_escape_string($_POST['sex']) : '';
       echo 'Gender: '. $sex;
?>