Select field or Text field - html

Question

I have a select with many options. If a user doesn't find value in option, He could fill a "other" field :
<select name="value">
<option>Choose...</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<input type="text" name="value">
In this case, if I choose a value in the select, it appeared blank beacause of the text fiel.
Thanks

Answer 1

I imagined it, needs to be improved
http://jsfiddle.net/neiesc/jv6qgn03/
<select name="value">
<option>Choose...</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<br />
<label for="chkOther">
Other
<input id="chkOther" type="checkbox" value="0" />
</label>
<input id="txtOther" type="text" name="value" disabled>
Javascript code:
$( "#chkOther" ).click(function() {
$( "#txtOther" ).prop( "disabled", !$( "#txtOther" ).prop( "disabled"));
});

Answer 2

Use different names for select and text input.
<form method="post">
<select name="select">
<option>Choose...</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<input type="text" name="field">
<input type="submit" name="submit">
</form>
And in PHP check what was chosen:
<?php
if (isset($_POST['submit'])) {
// form was sent
if (!empty($_POST['select'])) {
// select or both, use select
} elseif (!empty($_POST['input'])) {
// empty select txt input filled
} else {
// nothing chose in select and text input is blank
}
}
?>