Código:
<html> <head> <script LANGUAGE="javascript"> var capa function cambio(idCapa){ if (document.layers) capa = eval("document." + idCapa); if (document.all) capa = eval(idCapa + ".style"); if (document.getElementById) capa = eval('document.getElementById("' + idCapa + '").style'); if ((capa.visibility == "hidden") || (capa.visibility == "hide")){ capa.visibility = (document.layers) ? "show" : "visible" ; }else{ capa.visibility = (document.layers) ? "hide" : "hidden" ; } } //--> </script> </head> <body> <form name="busca" method="post" action="formulario.php?op=2"> <table width="80%" height="30" border="0" cellspacing="1"> <tr valign="top"> <td width="8%">Buscar</td> <td width="25%"><input type="text" name="buscar" size="30" /></td> <td width="5%"></td> <td width="62%" ><select name="opcion" onchange="if(this.value ==3) cambio(3);"> <option value="0"> </option> <option value="1" >Nro. Contenedor</option> <option value="2" >Nro. Documento</option> <option value="3" >Fecha</option> </select> </td> </tr> </table> <br/> <div id="3"> <table id="fecha" width="66%" border="0" cellspacing="0"> <tr> <td width="9%"> Inicio </td> <td width="36%"><input type="text" id="inicio" name="inicio"/> <button id="buttoninicio" >...</button></td> <td width="6%">Fin </td> <td width="39%"><input type="text" id="fin" name="fin"/> <button id="buttonfin" >...</button></td> </tr> </table> </div> <input type="submit" name="Button1" value="Ir" /> </body>