//---------------------------------------------------------------------------------------------------insertar

    
     $sql = "INSERT INTO $tbl ($names) VALUES ($values);";



			if (mysqli_query($con, $sql) === TRUE) {

    			//echo "Nuevo registro fue creado satisfactoreamente";

        header("location: index.php");

					} else {

    					echo "Error: " . $sql . "<br>" . mysqli_error($con);

					  }

			mysqli_close($con);

     //-----------------------------------------------------------------------------------------------------





    //---------------------------------------------------------------------------------------------Eliminar

		// sql para eliminar un registro

			$sql = "DELETE FROM $tbl WHERE id='" .$_POST['id']."'";

				if (mysqli_query($con, $sql)) {

    				//echo "Registro Eliminado";

            header("location: index.php");

					} else {

    					echo "Error deleting record: " . mysqli_error($con);

					  }

					mysqli_close($con);

     //-----------------------------------------------------------------------------






    //------------------------------------------------------------------------------------------------------------------------------------

		// sql para actualizar

		   $columnas = "nombre='". $_POST['nombre'] ."', email='". $_POST['email']."', face='". $_POST['face']."', whats= '".$_POST['whats']."'";

		

			$sql = "UPDATE $tbl SET $columnas WHERE id='" .$_POST['id']."'";

				if (mysqli_query($con, $sql)) {

    				//echo "Registro Actualizado";

            header("location: index.php");

					} else {

    					echo "Error deleting record: " . mysqli_error($con);

					  }

					mysqli_close($con);



          

  //----------------------------------------------------------------------------------------------------------------------------------------

//------------------------------------------------------------------




	   

//-----------------------------------------------------------------------------------------------------------------------vista



			   $sql = "SELECT * FROM $tbl";

				$rs = mysqli_query($con, $sql);



				while ($columna = mysqli_fetch_assoc($rs)) {

								                     

               echo "<tr><td><input type='radio' name='id' value='". $columna['id'] ."'>";    

    				echo "<td>".$columna['nombre']."</td>";

    				echo "<td>".$columna['email']."</td>";

    				echo "<td>".$columna['face']."</td>";

    				echo "<td>".$columna['whats']."</td>";

    				echo "<td><input class='btn btn-warning btn-sm' type='submit' name='action' value='Modificar'></td>";

    				echo "<td><input class='btn btn-danger btn-sm' type='submit' name='action' value='Eliminar'></td></tr>";    

             }
//------------------------------------------------------------------------------------------------------------------------
            


//------------------------------------------------------------------------------------------lectura dbr

  /**

  * muestra un registro pasado por valor id

  * @param: int

  * @return: array

  */ 

  function showAlumno($id){

   global $con, $tbl;

     

            $sql = "select * from $tbl where id=$id";

				$result = mysqli_query($con, $sql) or die (mysqli_error($con));

				$row = mysqli_fetch_assoc($result);

				//print_r($row);

				return $row;

  }

//------------------------------------------------------------------------------------------------