Binding a Windows DataGrid to Master-Detail Data

The sample uses eight stored procedures, which are shown in Example 7-20 through Example 7-27: GetOrders Used to retrieve a single record from the Orders table if the optional @OrderId

[ Team LiB ]

Recipe 7.12 Binding a Windows DataGrid to Master-Detail Data

Problem

You need to bind both a parent table and child table within a DataSet to a DataGrid so that the child data is displayed when the parent is expanded, and update the database with edits made to data in both tables

Solution

Use the approach demonstrated in the sample code

The sample uses eight stored procedures, which are shown in Example 7-20 through Example 7-27:

GetOrders

Used to retrieve a single record from the Orders table if the optional @OrderId

parameter is specified or all Orders records if it is not

DeleteOrders

Used to delete the record specified by the @OrderId parameter from the Orders

table

InsertOrders

Used to insert a record into the Orders table and return the OrderID identity value for the new record

UpdateOrders

Used to update all field values for the record in the Orders table specified by the

@OrderId input parameter

GetOrderDetails

Used to retrieve a single record from the Order Details table if the optional

@OrderId and @ProductID parameters are specified, or all Order Details records

if it is not

DeleteOrderDetails

Used to delete the record specified by the @OrderId and @ProductID parameters

from the Order Details table

InsertOrderDetails

Used to insert a record into the Order Details table

UpdateOrderDetails

Used to update all field values for the record in the Order Details table specified

by the @OrderId and @ProductID input parameters

Example 7-20 Stored procedure: GetOrders

CREATE PROCEDURE GetOrders

@OrderID int=null

AS

SET NOCOUNT ON

if @OrderID is not null

begin

select

OrderID,

CustomerID,

EmployeeID,

OrderDate,

RequiredDate,

ShippedDate,

ShipVia,

Freight,

ShipName,

ShipAddress,

ShipCity,

ShipRegion,

ShipPostalCode,

ShipCountry

from

Orders

where

OrderID=@OrderID

return 0

end

select

OrderID,

CustomerID,

EmployeeID,

OrderDate,

RequiredDate,

ShippedDate,

ShipVia,

Freight,

ShipName,

ShipAddress,

ShipCity,

ShipRegion,

ShipPostalCode,

ShipCountry

from

Orders

return 0

Example 7-21 Stored procedure: DeleteOrders

CREATE PROCEDURE DeleteOrders

@OrderID int

AS

SET NOCOUNT ON

delete

from

Orders

where

OrderID=@OrderID

return 0

Example 7-22 Stored procedure: InsertOrders

CREATE PROCEDURE InsertOrders

@OrderID int output,

@CustomerID nchar(5),

@EmployeeID int,

@OrderDate datetime,

@RequiredDate datetime, @ShippedDate datetime,

@ShipVia int,

@Freight money,

@ShipName nvarchar(40), @ShipAddress nvarchar(60), @ShipCity nvarchar(15),

@ShipRegion nvarchar(15), @ShipPostalCode nvarchar(10), @ShipCountry nvarchar(15)

AS

SET NOCOUNT ON

insert Orders(

CustomerID,

EmployeeID,

OrderDate,

RequiredDate,

ShippedDate,

ShipVia,

Freight,

ShipName,

ShipAddress,

ShipCity,

ShipRegion,

ShipPostalCode,

ShipCountry)

values (

@CustomerID,

@EmployeeID,

@OrderDate,

@RequiredDate,

@ShippedDate,

@ShipVia,

@Freight,

@ShipName,

@ShipAddress,

@ShipCity,

@ShipRegion,

@ShipPostalCode,

@ShipCountry)

if @@rowcount=0

return 1

set @OrderID=Scope_Identity( )

select @OrderId OrderId

return 0

Example 7-23 Stored procedure: UpdateOrders

CREATE PROCEDURE UpdateOrders

@OrderID int,

@CustomerID nchar(5),

@EmployeeID int,

@OrderDate datetime,

@RequiredDate datetime,

@ShippedDate datetime,

@ShipVia int,

@Freight money,

@ShipName nvarchar(40),

@ShipAddress nvarchar(60),

@ShipCity nvarchar(15),

@ShipRegion nvarchar(15),

@ShipPostalCode nvarchar(10),

@ShipCountry nvarchar(15)

AS

SET NOCOUNT ON

update

Orders

set

CustomerID=@CustomerID,

EmployeeID=@EmployeeID,

OrderDate=@OrderDate,

RequiredDate=@RequiredDate,

ShippedDate=@ShippedDate,

ShipVia=@ShipVia,

Freight=@Freight,

ShipName=@ShipName,

ShipAddress=@ShipAddress,

ShipCity=@ShipCity,

ShipRegion=@ShipRegion,

ShipPostalCode=@ShipPostalCode,

ShipCountry=@ShipCountry

where

OrderID=@OrderID

if @@rowcount=0

return 1

return 0

Example 7-24 Stored procedure: GetOrderDetails

CREATE PROCEDURE GetOrderDetails

@OrderID int=null,

@ProductID int=null

AS

SET NOCOUNT ON

if @OrderID is not null and @ProductID is not null begin

select

OrderID,

ProductID,

UnitPrice,

Quantity,

Discount

from

[Order Details]

where

OrderID=@OrderID and

ProductID=@ProductID

return 0

end

select

OrderID,

ProductID,

UnitPrice,

Quantity,

Discount

from

[Order Details]

return 0

Example 7-25 Stored procedure: DeleteOrderDetails

CREATE PROCEDURE DeleteOrderDetails

@OrderID int,

@ProductID int

AS

SET NOCOUNT ON

delete

from

[Order Details]

where

OrderID=@OrderID and

ProductID=@ProductID

return 0

Example 7-26 Stored procedure: InsertOrderDetails

CREATE PROCEDURE InsertOrderDetails

@OrderID int,

@ProductID int,

@UnitPrice money,

@Quantity smallint,

@Discount real

AS

SET NOCOUNT ON

insert [Order Details](

OrderID,

ProductID,

UnitPrice,

Quantity,

Discount)

values (

@OrderID,

@ProductID,

@UnitPrice,

@Quantity,

@Discount)

if @@rowcount=0

return 1

return 0

Example 7-27 Stored procedure: UpdateOrderDetails

CREATE PROCEDURE UpdateOrderDetails

@OrderID int,

@ProductID int,

@UnitPrice money,

@Quantity smallint,

@Discount real

AS

SET NOCOUNT ON

update

[Order Details]

set

UnitPrice=@UnitPrice,

Quantity=@Quantity,

Discount=@Discount

where

OrderID=@OrderID and

ProductID=@ProductID

if @@rowcount=0

return 1

return 0

The sample code contains two event handlers:

Form.Load

Sets up the sample by creating a DataSet containing the Orders and Order Details DataTable objects A DataRelation object is created relating the tables

DataAdapter objects are created for each DataTable; the select, delete, insert, and update Command objects are specified for each using the custom logic in the eight stored procedures used by this solution The DataAdapter objects are used to fill both tables in the DataSet Finally, the default view of the Orders table is bound to

the data grid on the form

Update Button.Click

Uses the DataAdapter for the Orders and Order Details DataTable objects to update offline changes back to the database

The C# code is shown in Example 7-28

Example 7-28 File: HierarchicalDataGridForm.cs

// Namespaces, variables, and constants

using System;

using System.Configuration;

using System.Data;

using System.Data.SqlClient;

private DataSet ds;

// Private SqlDataAdapter daParent, daChild

private SqlDataAdapter daOrder, daOrderDetail;

// Table name constants

private const String ORDERS_TABLE = "Orders";

private const String ORDERDETAILS_TABLE = "OrderDetails";

// Relation name constants

private const String ORDERS_ORDERDETAILS_RELATION =

"Orders_OrderDetails_Relation";

// Field name constants for Orders table

public const String ORDERID_FIELD = "OrderID";

public const String CUSTOMERID_FIELD = "CustomerID";

public const String EMPLOYEEID_FIELD = "EmployeeID";

public const String ORDERDATE_FIELD = "OrderDate";

public const String REQUIREDDATE_FIELD = "RequiredDate";

public const String SHIPPEDDDATE_FIELD = "ShippedDate";

public const String SHIPVIA_FIELD = "ShipVia";

public const String FREIGHT_FIELD = "Freight";

public const String SHIPNAME_FIELD = "ShipName";

public const String SHIPADDRESS_FIELD = "ShipAddress";

public const String SHIPCITY_FIELD = "ShipCity";

public const String SHIPREGION_FIELD = "ShipRegion";

public const String SHIPPOSTALCODE_FIELD = "ShipPostalCode";

public const String SHIPCOUNTRY_FIELD = "ShipCountry";

// Stored procedure name constants

public const String DELETEORDERS_SP = "DeleteOrders";

public const String GETORDERS_SP = "GetOrders";

public const String INSERTORDERS_SP = "InsertOrders";

public const String UPDATEORDERS_SP = "UpdateOrders";

// Stored procedure parameter name constants for Orders table

public const String ORDERID_PARM = "@OrderID";

public const String CUSTOMERID_PARM = "@CustomerID";

public const String EMPLOYEEID_PARM = "@EmployeeID";

public const String ORDERDATE_PARM = "@OrderDate";

public const String REQUIREDDATE_PARM = "@RequiredDate";

public const String SHIPPEDDDATE_PARM = "@ShippedDate";

public const String SHIPVIA_PARM = "@ShipVia";

public const String FREIGHT_PARM = "@Freight";

public const String SHIPNAME_PARM = "@ShipName";

public const String SHIPADDRESS_PARM = "@ShipAddress";

public const String SHIPCITY_PARM = "@ShipCity";

public const String SHIPREGION_PARM = "@ShipRegion";

public const String SHIPPOSTALCODE_PARM = "@ShipPostalCode"; public const String SHIPCOUNTRY_PARM = "@ShipCountry";

// Field name constants for OrderDetails table

public const String ORDERID_FIELD = "OrderID";

public const String PRODUCTID_FIELD = "ProductID";

public const String UNITPRICE_FIELD = "UnitPrice";

public const String QUANTITY_FIELD = "Quantity";

public const String DISCOUNT_FIELD = "Discount";

// Stored procedure name constants

public const String DELETEORDERDETAILS_SP = "DeleteOrderDetails"; public const String GETORDERDETAILS_SP = "GetOrderDetails";

public const String INSERTORDERDETAILS_SP = "InsertOrderDetails"; public const String UPDATEORDERDETAILS_SP = "UpdateOrderDetails";

// Stored procedure parameter name constants for OrderDetails table

public const String ORDERID_PARM = "@OrderID";

public const String PRODUCTID_PARM = "@ProductID";

public const String UNITPRICE_PARM = "@UnitPrice";

public const String QUANTITY_PARM = "@Quantity";

public const String DISCOUNT_PARM = "@Discount";

//

private void HierarchicalDataGridForm_Load(object sender,

System.EventArgs e)

{

ds = new DataSet( );

// Fill the Order table and add it to the DataSet

daOrder = new SqlDataAdapter(GETORDERS_SP,

ConfigurationSettings.AppSettings["Sql_ConnectString"]);

daOrder.SelectCommand.CommandType = CommandType.StoredProcedure; DataTable dtOrder = new DataTable(ORDERS_TABLE);

daOrder.FillSchema(dtOrder, SchemaType.Source);

daOrder.Fill(dtOrder);

ds.Tables.Add(dtOrder);

// Fill the OrderDetails table with schema and add it to the DataSet

daOrderDetail = new SqlDataAdapter(GETORDERDETAILS_SP,

ConfigurationSettings.AppSettings["Sql_ConnectString"]);

daOrderDetail.SelectCommand.CommandType = CommandType.StoredProcedure; DataTable dtOrderDetail = new DataTable(ORDERDETAILS_TABLE);

daOrderDetail.FillSchema(dtOrderDetail, SchemaType.Source);

daOrderDetail.Fill(dtOrderDetail);

ds.Tables.Add(dtOrderDetail);

// Create a relation between the tables

ds.Relations.Add(ORDERS_ORDERDETAILS_RELATION,

ds.Tables[ORDERS_TABLE].Columns[ORDERID_FIELD],

ds.Tables[ORDERDETAILS_TABLE].Columns[ORDERID_FIELD],

true);

// Build the orders delete command

SqlCommand deleteCommand = new SqlCommand(DELETEORDERS_SP,

daOrder.SelectCommand.Connection);

deleteCommand.CommandType = CommandType.StoredProcedure;

SqlParameterCollection sqlParams = deleteCommand.Parameters;

sqlParams.Add(ORDERID_PARM, SqlDbType.Int, 0, ORDERID_FIELD);

daOrder.DeleteCommand = deleteCommand;

// Build the orders insert command

SqlCommand insertCommand = new SqlCommand(INSERTORDERS_SP,

daOrder.SelectCommand.Connection);

insertCommand.CommandType = CommandType.StoredProcedure;

sqlParams = insertCommand.Parameters;

sqlParams.Add(ORDERID_PARM, SqlDbType.Int, 0,

ORDERID_FIELD).Direction = ParameterDirection.Output;

sqlParams.Add(CUSTOMERID_PARM, SqlDbType.NChar, 5,

CUSTOMERID_FIELD);

sqlParams.Add(EMPLOYEEID_PARM, SqlDbType.Int, 0, EMPLOYEEID_FIELD); sqlParams.Add(ORDERDATE_PARM, SqlDbType.DateTime, 0,

ORDERDATE_FIELD);

sqlParams.Add(REQUIREDDATE_PARM, SqlDbType.DateTime, 0,

REQUIREDDATE_FIELD);

sqlParams.Add(SHIPPEDDDATE_PARM, SqlDbType.DateTime, 0,

SHIPPEDDDATE_FIELD);

sqlParams.Add(SHIPVIA_PARM, SqlDbType.Int, 0, SHIPVIA_FIELD);

sqlParams.Add(FREIGHT_PARM, SqlDbType.Money, 0, FREIGHT_FIELD);

sqlParams.Add(SHIPNAME_PARM, SqlDbType.NVarChar, 40,

SHIPNAME_FIELD);

sqlParams.Add(SHIPADDRESS_PARM, SqlDbType.NVarChar, 60,

SHIPADDRESS_FIELD);

sqlParams.Add(SHIPCITY_PARM, SqlDbType.NVarChar, 15, SHIPCITY_FIELD); sqlParams.Add(SHIPREGION_PARM, SqlDbType.NVarChar, 15,

SHIPREGION_FIELD);

sqlParams.Add(SHIPPOSTALCODE_PARM, SqlDbType.NVarChar, 10,

SHIPPOSTALCODE_FIELD);

sqlParams.Add(SHIPCOUNTRY_PARM, SqlDbType.NVarChar, 15,

SHIPCOUNTRY_FIELD);

daOrder.InsertCommand = insertCommand;

// Build the orders update command

SqlCommand updateCommand = new SqlCommand(UPDATEORDERS_SP,

daOrder.SelectCommand.Connection);

updateCommand.CommandType = CommandType.StoredProcedure;

sqlParams = updateCommand.Parameters;

sqlParams.Add(ORDERID_PARM, SqlDbType.Int, 0, ORDERID_FIELD);

sqlParams.Add(CUSTOMERID_PARM, SqlDbType.NChar, 5,

CUSTOMERID_FIELD);

sqlParams.Add(EMPLOYEEID_PARM, SqlDbType.Int, 0, EMPLOYEEID_FIELD); sqlParams.Add(ORDERDATE_PARM, SqlDbType.DateTime, 0,

ORDERDATE_FIELD);

sqlParams.Add(REQUIREDDATE_PARM, SqlDbType.DateTime, 0,

REQUIREDDATE_FIELD);

sqlParams.Add(SHIPPEDDDATE_PARM, SqlDbType.DateTime, 0,

SHIPPEDDDATE_FIELD);