<form id="form1" name="form1" method="post" action="">
  <select name="select" id="select">
    <option selected="selected">请选择</option>
    <option value="11111111">11111111</option>
    <option value="22222222">22222222</option>
  </select>
  <input type="submit" name="button" id="button" value="搜索" />
</form>

应该这样才行。