不读取Php文本框数据

I am trying to get data from html form in php. this is my html code.

<div id="search_specify">
    <?php echo form_open('search/advanced_search');?>
        <a class="srch_heading">Keyword</a>
        <input name="key" class="srch_box" type="text" />
        <br />
        <br />
        <a class="srch_heading">First Name</a>
        <input name="first" class="srch_box" type="text" />
        <br />
        <br />
        <a class="srch_heading">Last Name</a>
        <input name="last" class="srch_box" type="text"/>
        <br />
        <br />
        <a class="srch_heading">Company</a>
        <input name="company" class="srch_box" type="text"/>
        <br />
        <br />
        <a class="srch_heading">Country</a><br />
        <select name="country" class="slct_box"/>
            <option>aaa</option>
        </select>
    <?php echo form_submit('submit','Search') ?>
</div>

this is my php code

$key=$_POST['key'];
$first=$_POST['first'];
$last=$_POST['last'];
$company=$_POST['company'];
$country=$_POST['country'];

echo $first;
echo $last;
echo $company;
echo $key;
echo$country;

the values of key, company and country are read fine but the code did not get the value of first and last

This the the page source code

<form action="http://localhost/ok/index.php/search/advanced_search" method="post" accept-charset="utf-8"><a class="srch_heading">Keyword</a>
    <input name="key" class="srch_box" type="text" />
    <br />
    <br />
    <a class="srch_heading">First Name</a>
    <input name="first" class="srch_box" type="text" />
    <br />
    <br />
    <a class="srch_heading">Last Name</a>
    <input name="last" class="srch_box" type="text"/>
    <br />
    <br />
    <a class="srch_heading">Company</a>
    <input name="company" class="srch_box" type="text"/>
    <br />
    <br />
    <a class="srch_heading">Country</a><br />
    <select name="country" class="slct_box"/>
        <option>aaa</option>
    </select>
    <input type="submit" name="submit" value="Search"/></div>
</form>

Please help

I was not closing the form. That was causing the trouble. So i added <?php echo form_close();?> after <?php echo form_submit('submit','Search') ?> And problem solved!

You can try this code in you php file.

echo $this->input->post('first'); 

It will give your all post data.