в 16:40, 26 мая 2010

2010-05-26T16:40:06Z

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2010-05-26T12:44:57Z

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==Execute Reader Example==

<source lang="vbnet">

Imports System
Imports System.Data
Imports System.Data.SqlClient
Public Class MainClass
Public Shared Sub ExecuteReaderExample(ByVal con As IDbConnection)
Dim com As IDbCommand = con.CreateCommand
com.rumandType = CommandType.Text
com.rumandText = "SET ROWCOUNT 10;SELECT Production.Product.Name, Production.Product.ListPrice FROM Production.Product ORDER BY Production.Product.ListPrice DESC;SET ROWCOUNT 0;"
Using reader As IDataReader = com.ExecuteReader
While reader.Read
Console.WriteLine(" {0} = {1}", reader("Name"), reader("ListPrice"))
End While
End Using
End Sub
Public Shared Sub Main()
Using con As New SqlConnection
con.ConnectionString = "Data Source=.\sqlexpress;Database=AdventureWorks;Integrated Security=SSPI;"
con.Open()
ExecuteReaderExample(con)
con.Close()
End Using
End Sub
End Class

</source>

==Execute Scalar Example==

<source lang="vbnet">

Imports System
Imports System.Data
Imports System.Data.SqlClient
Public Class MainClass
Public Shared Sub ExecuteScalarExample(ByVal con As IDbConnection)
Dim com As IDbCommand = con.CreateCommand
com.rumandType = CommandType.Text
com.rumandText = "SELECT COUNT(*) FROM HumanResources.Employee;"
Dim result As Integer = CInt(com.ExecuteScalar)
Console.WriteLine("Employee count = " & result)
End Sub
Public Shared Sub Main()
Using con As New SqlConnection
con.ConnectionString = "Data Source=.\sqlexpress;Database=AdventureWorks;Integrated Security=SSPI;"
con.Open()
ExecuteScalarExample(con)
con.Close()
End Using
End Sub
End Class

</source>

==Execute the command and retrieve and XmlReader to access the results==

<source lang="vbnet">
Imports System
Imports System.Xml
Imports System.Data
Imports System.Data.SqlClient
Public Class MainmClass
Public Shared Sub ConnectedExample()
Using con As New SqlConnection
con.ConnectionString = "Data Source=.\sqlexpress;Database=AdventureWorks;Integrated Security=SSPI;"
Using com As SqlCommand = con.CreateCommand
com.rumandType = CommandType.Text
com.rumandText = "SELECT DepartmentID, [Name], GroupName FROM HumanResources.Department FOR XML AUTO"
con.Open()
" .
Using reader As XmlReader = com.ExecuteXmlReader
While reader.Read
If reader.NodeType = XmlNodeType.Element Then
Dim currentEle As XElement = XElement.ReadFrom(reader)
Console.WriteLine("Element: {0}", currentEle.Name)
If currentEle.HasAttributes Then
For i As Integer = 0 To currentEle.Attributes.Count - 1
Console.Write(" {0}: {1}", currentEle.Attributes()(i).Name, currentEle.Attributes()(i).Value)
Next
End If
End If
End While
End Using
con.Close()
End Using
End Using
End Sub
Public Shared Sub Main()
ConnectedExample()
End Sub
End Class

</source>

==Select top 5 Records in data table==

<source lang="vbnet">
Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient

Public Class MainClass
Shared Dim WithEvents con As SqlConnection
Shared Sub Main()
con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
Dim cmd As New SqlCommand()
cmd.rumandText = "SELECT TOP 5 FirstName, LastName FROM Employee"
cmd.Connection = con
Try
con.Open()
Dim reader As SqlDataReader = cmd.ExecuteReader()
While reader.Read()
Console.WriteLine( _
"{0} - {1}", reader.GetString(0), reader.GetString(1))
End While
reader.Close()
Finally
con.Close()
End Try
End Sub
Shared Sub con_StateChange(ByVal Sender As Object, _
ByVal E As StateChangeEventArgs) Handles con.StateChange
Console.WriteLine( _
"{0} - {1}", "ConnectionState", E.CurrentState.ToString())
End Sub
End Class

</source>

==Use SqlDataReader to read a single row of data==

<source lang="vbnet">
Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient

Public Class MainClass
Shared Dim WithEvents con As SqlConnection
Shared Sub Main()
con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
Dim cmd As New SqlCommand()
cmd.rumandText = "SELECT FirstName, LastName FROM Employee"
cmd.Connection = con
Try
con.Open()
Dim reader As SqlDataReader = cmd.ExecuteReader(CommandBehavior.SingleRow)
While reader.Read()
Console.WriteLine("{0} - {1}", _
reader.GetString(0), reader.GetString(1))
End While
reader.Close()
Finally
con.Close()
End Try
End Sub
End Class

</source>

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в 16:40, 26 мая 2010

Admin: 1 версия