ADO.NETADO.NETAccess Data Object (cont.)

DataSet

DataTable

DataTable

DataTable

What is a Dataset?

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SQL Server 2000

Physical storage

OleDb Database

SqlDataAdapter

SqlConnection

Web server memory

OleDbDataAdapter

OleDbConnection

Data Adapters

SelectCommand UpdateCommand InsertCommand DeleteCommand

DataAdapter

DataSet

DataReader

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sp_SELECT

Command Command Command Command

Connection

sp_UPDATE sp_INSERT sp_DELETE

Database

DataReaderDataReader

• Store the query in a DataAdapter

� SelectCommand Properties

DataAdapter

da.SelectCommand.CommandText da.SelectCommand.Connection

SqlDataAdapter da = new SqlDataAdapter("select * from Authors",conn);

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� Definir os comandos InsertCommand, UpdateCommand, and DeleteCommand, se necessário

da.SelectCommand.Connection

da.Insertcommandda.UpdateCommand

Creating a DataSet

� Create a DataSet

� Fill – executa o SelectCommand

� Access a DataTable

DataSet ds = new DataSet();da.Fill(ds, "Authors");

ds.Tables["Authors"].Rows.Count;

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ds.Tables["Authors"].Rows.Count;

string str="";

foreach(DataRow r in ds.Tables["Authors"].Rows)

{str += r[2];str += r["au_lname"];

}

DataAdapder / DataSet

string strconn="Provider=Microsoft.Jet.OLEDB.4.0;

….

String strsql=

"Select * from Produtos where IdCat=“ + id;

conn=new OleDbConnection();

• DataSource de um Controlo

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conn=new OleDbConnection();

conn.ConnectionString=strconn;

OleDbDataAdapter da;

da = new OleDbDataAdapter (strsql,conn);

DataSet ds= new DataSet();

da.Fill(ds,”Produtos”); //Populating DataSet

gvProdutos.DataSource=ds;

gvProdutos.DataBind();

DataAdapder / DataSet

� Aceder às tabelas no DataSet

� Usar Tables para aceder à tabela Produtos

� Objecto DataTable

DataTable dt =dataset.Tables[“Produtos"]

� Aceder às linhas da tabela

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� Aceder às linhas da tabela

� Usar Rows

� Objecto DataRow

DataRow dr= dataset.Tables["Produtos”].Rows[0];

foreach (DataRow dr in dataset.Tables[“Produtos"].Rows)

…

Data-Bound Web Server Controls

� ASP.NET Data-Bound Web Server Controls

� GridViewdisplays data as a table and provides the capability to sort

columns, page through data, and edit or delete a single record

� DetailsViewrenders a single record at a time as a table and provides the

capability to page through multiple records, as well as to insert,

update, and delete records.update, and delete records.

� FormViewrenders a single record at a time from a data source and provides

the capability to page through multiple records, as well as to insert,

update, and delete records. FormView control does not specify a

built-in layout.

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Data-Bound Web Server Controls

� Repeaterrenders a read-only list from a set of records returned from a data

source. Repeater control does not specify a built-in layout.

� DataListrenders data as table and enables you to display data records in

different layouts, such as ordering them in columns or rows

ASP.NET Data-Bound Web Server Controls Overview

https://msdn2.microsoft.com/en-us/library/ms228214.aspx

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Data-Bound Web Server Controls

� Edit, Update, Delete e Insert num Data-Bound

Web Server Controls

� Exemplificado com um DetailView

� As propriedades e eventos são semelhantespara os outros controlos

� Todos os métodos não estão protegidos para � Todos os métodos não estão protegidos para salientar o código ADO e programação dos eventos

� Cada método deveria:

� Tratar excepções

� Validar parâmetros de entrada

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DetailsView

� Populate DetailsView

void bindDetailView()

{

DataAccess dal = new DataAccess();

DataSet ds = dal.getDatasetProdutos();

DetailsView1.DataSource = ds;

DetailsView1.DataBind();

} }

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� DetailsView Configuration

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DetailsView

� Events:� DataBinding Occurs when the server control binds to a

data source. (inherited from Control)

� ItemCreated Occurs when a record is created in a DetailsView control.

� ItemDeleted Occurs when a Delete button within a DetailsView control is clicked, but after the delete operation.

ItemDeleting Occurs when a Delete button within a � ItemDeleting Occurs when a Delete button within a DetailsView control is clicked, but before the delete operation.

� ItemInserting Occurs when an Insert button within a DetailsView control is clicked, but before the insert operation.

� ItemUpdated Occurs when an Update button within a DetailsView control is clicked, but after the update operation.

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Events:

� ItemUpdating Occurs when an Update button within a DetailsView control is clicked, but before the update operation.

� Load Occurs when the server control is loaded into the Pageobject. (inherited from Control)

� ModeChanging Occurs when a DetailsView control attempts to change between edit, insert, and read-only mode, but before the CurrentMode property is updated.

� PageIndexChanged Occurs when the value of the PageIndex� PageIndexChanged Occurs when the value of the PageIndexproperty changes after a paging operation.

� PageIndexChanging Occurs when the value of the PageIndexproperty changes before a paging operation.

� …

http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.detailsview_events.aspx

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DetailsView

� Paging

� Property: AllowPaging=true;

� Event : PageIndexChanging

� Property: PageIndex

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protected void DetailsView1_PageIndexChanging(object

sender, DetailsViewPageEventArgs e)

{

DetailsView1.PageIndex = e.NewPageIndex;

bindDetailView();

}

DetailsView

� Edit� Property: AutoGenerateEditButton=true;

� Event: ModeChanging

� Property: DetailsViewMode (Edit, Insert,

ReadOnly )

protected void DetailsView1_ModeChanging(object sender,

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protected void DetailsView1_ModeChanging(object sender, DetailsViewModeEventArgs e)

{

if ( e.NewMode == DetailsViewMode.Edit)

{

DetailsView1.ChangeMode(DetailsViewMode.Edit);

}

else if (DetailsView1.CurrentMode == DetailsViewMode.Edit

&& e.CancelingEdit)

{

DetailsView1.ChangeMode(DetailsViewMode.ReadOnly);

}

...

DetailsView

� DetailsView Structure (GridView, FormView, etc)

� Contains a collection of Rows

� Row contains a collection of Cells

� Cell contains a collection of Controls

Rows[0]

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Cells[1]

Controls[0] –> (TextBox)

nome=((TextBox)DetailsView1.Rows[2].Cells[1].Controls[0]).Text;

Cells[0]

DetailsView Fields Values

protected void getDetailsView_Values()

{

idcat =

Convert.ToInt32(((TextBox)DetailsView1.Rows[1].Cells[1].

Controls[0]).Text);

nome =

((TextBox)DetailsView1.Rows[2].Cells[1].Controls[0]).Text;

preco =

Convert.ToDouble(((TextBox)DetailsView1.Rows[3].Cells[1]

. Controls[0]).Text);

stock =

Convert.ToInt32(((TextBox)DetailsView1.Rows[4].Cells[1].

Controls[0]).Text);

}

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DetailsView

� Update

� Event: ItemUpdating

protected void DetailsView1_ItemUpdating(object sender, DetailsViewUpdateEventArgs e)

{

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int idprod =

Convert.ToInt32(DetailsView1.DataKey.Value);

DataAccess dal = new DataAccess();

getDetailsViewValues();

dal.updateProduct(idprod,idcat,nome,preco,stock);DetailsView1.ChangeMode(DetailsViewMode.ReadOnly);

bindDetailView();

}

DetailsView

� Insert ( New)

� Property: AutoGenerateInsertButton

� Event: ItemInserting

protected void DetailsView1_ItemInserting(object

sender, DetailsViewInsertEventArgs e)sender, DetailsViewInsertEventArgs e)

{

DataAccess dal = new DataAccess();

getDetailsViewValues();

dal.insertProduct(idcat, nome, preco, stock);

DetailsView1.ChangeMode(DetailsViewMode.ReadOnly);

bindDetailView();

}

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DetailsView

� Delete� Property: AutoGenerateDeleteButton=true;

� Event: ItemDeleting

protected void DetailsView1_ItemDeleting(object

sender, DetailsViewDeleteEventArgs e)

{{

DataAccess dal = new DataAccess();

int idprod =

Convert.ToInt32(DetailsView1.DataKey.Value);

dal.deleteProduct(idprod);

bindDetailView();

}

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Métodos na Class Data Access Layer

� getConnection

private OleDbConnection getConnection()

{

string strcon = DEFAULT_CONN + DEFAULT_DBPATH;

OleDbConnection conn = new OleDbConnection();

conn.ConnectionString = strcon;

conn.Open();conn.Open();

return conn;

}

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Métodos na Classe Data Access Layer

� getDatasetProduts

public DataSet getDatasetProdutos()

{

OleDbConnection conn = getConnection();

OleDbCommand cmd = new OleDbCommand();

cmd.Connection = conn;

string strsql = "select * from Produtos ";string strsql = "select * from Produtos ";

cmd.CommandText = strsql;

OleDbDataAdapter da = new OleDbDataAdapter();

da.SelectCommand = cmd;

DataSet ds = new DataSet();

da.Fill(ds);

return ds;

}

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Métodos na Class Data Access Layer

� updateProduct

public int updateProduct(int idprod, int idcat,string

nomeprod,double preco, int stock)

{ string strsql = "update Produtos SET IdCat=? ,

NomeProd=? , Preco=? , Stock=? where IdProd=?";

OleDbConnection conn = getConnection();

OleDbCommand cmd = new OleDbCommand();

cmd.Connection = conn;

cmd.CommandText = strsql;

cmd.Parameters.AddWithValue("idcat", idcat);

…

cmd.Parameters.AddWithValue("stock", stock);

cmd.Parameters.AddWithValue("idprod", idprod);

int result=cmd.ExecuteNonQuery();

conn.Close();

return result;

}23

Class Data Access Layer

� insertProduct

public int insertProduct( int idcat, string nomeprod,

double preco, int stock){

string strsql = "insert into Produtos (IdCat, NomeProd

, Preco , Stock ) values(?,?,?,?)";

OleDbConnection conn = getConnection();

OleDbCommand cmd = new OleDbCommand();

cmd.Connection = conn;cmd.Connection = conn;

cmd.CommandText = strsql;

cmd.Parameters.AddWithValue("idcat", idcat);

cmd.Parameters.AddWithValue("nomeprod", nomeprod);

cmd.Parameters.AddWithValue("preco", preco);

cmd.Parameters.AddWithValue("stock", stock);

int idprod = cmd.ExecuteNonQuery();

conn.Close();

return idprod;

}24

Class Data Access Layer

� deleteProduct

public int deleteProduct(int idprod)

{

string strsql = "Delete from Produtos where IdProd=?";

OleDbConnection conn = getConnection();

OleDbCommand cmd = new OleDbCommand();

cmd.Connection = conn;

cmd.CommandText = strsql;

cmd.Parameters.AddWithValue("idprod", idprod);

int res = cmd.ExecuteNonQuery();

conn.Close();

return res;

}

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