Untitled Page

DATAREADER

Categories:

Products:

ProductID	ProductName	UnitPrice	UnitsInStock
1	notebook	1500.0000	17
2	Coca-Cola 111	4.0000	4
24	Guaraná Fantástica	4.5000	20
34	Sasquatch	14.0000	111
35	Steeleye Stout	18.0000	20
38	Côte de Blaye	263.5000	17
39	Chartreuse verte	18.0000	69
43	Ipoh Coffee	46.0000	17
67	Laughing Lumberjack Lager	14.0000	52
70	Outback Lager	100.0000	15
75	Rhönbräu Klosterbier	7.7500	125
76	Lakkalikööri	18.0000	57

Show code / exibir código

using System.Data.SqlClient;
using System.Web.Configuration;

string conStr = WebConfigurationManager.ConnectionStrings["ConnStringKey"].ConnectionString;

protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
string sql = "Select CategoryID, CategoryName FROM Categories ORDER BY CategoryName";
SqlConnection conn = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand(sql, conn);
try
{
conn.Open();
SqlDataReader reader = cmd.ExecuteReader();
dropCategories.DataSource = reader;
dropCategories.DataValueField = "CategoryID";
dropCategories.DataTextField = "CategoryName";
dropCategories.DataBind();
reader.Close();
dropCategories_SelectedIndexChanged(sender, e);
}
finally
{
conn.Close();
}
}
}

protected void dropCategories_SelectedIndexChanged(object sender, EventArgs e)
{
string sql = "Select ProductID, ProductName, UnitPrice, UnitsInStock FROM Products Where CategoryID=@cat";
SqlConnection conn = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand(sql, conn);
SqlParameter p1 = new SqlParameter("@cat", SqlDbType.Int);
p1.Value = dropCategories.SelectedItem.Value;
cmd.Parameters.Add(p1);
try
{
conn.Open();
SqlDataReader reader = cmd.ExecuteReader();
griddata.DataSource = reader;
griddata.DataBind();
reader.Close();
}
finally
{
conn.Close();
}
}

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