<div id="buy-buttons">
  <label>Quantity:</label>
  <input name="txtQuantity" id="txtQuantity" type="text" value="1" />
  <input type="submit" name="btnAddToCart" value="Add To Cart" id="btnAddToCart" />
</div>
 
<script>
// First way:
$("#txtQuantity").remove();
$("#buy-buttons").append('<select name="txtQuantity" id="txtQuantity"></select>');
$("#txtQuantity").append('<option value="1" selected="selected">1</option>' +
    '<option value="2">2</option>' +
    '<option value="3">3</option>' +
    '<option value="4">4</option>' +
    '<option value="5">5</option>');
 
// Second way:
$("#txtQuantity")
    .replaceWith('<select name="txtQuantity" id="txtQuantity">' +
        '<option value="1">1</option>' +
        '<option value="2">2</option>' +
        '<option value="3">3</option>' +
        '<option value="4">4</option>' +
        '<option value="5">5</option>' +
        '</select>');
</script>

http://www.apphp.com/index.php?snippet=javascript-converting-text-input-to-select

Sometimes you need the page dynamically changes a texbox with a dropdown box. On the example below we show you how to perform this work. The first way demonstrates how to do this with remove() and append() jQuery methods and the second shows how to perform the same work with replaceWith() method.

Converting a text input to a select with JavaScript

javascript

JavaScript