ExecuteReader() in SqlCommand Object send the SQL statements to Connection Object and populate a SqlDataReader Object based on the SQL statement. When the ExecuteReader method in SqlCommand Object execute , it instantiate a SqlClient.SqlDataReader Object.
The SqlDataReader Object is a stream-based , forward-only, read-only retrieval of query results from the Data Source, which do not update the data. The SqlDataReader cannot be created directly from code, they created only by calling the ExecuteReader method of a Command Object.
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim cnn As SqlConnection
Dim cmd As SqlCommand
Dim sql As String
Dim reader As SqlDataReader
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
sql = "Your SQL Statement Here , like Select * from product"
cnn = New SqlConnection(connetionString)
Try
cnn.Open()
cmd = New SqlCommand(sql, cnn)
reader = cmd.ExecuteReader()
While reader.Read()
MsgBox(reader.Item(0) & " - " & reader.Item(1) & " - " & reader.Item(2))
End While
reader.Close()
cmd.Dispose()
cnn.Close()
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
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connetionString = "Data Source = ServerName; Initial Catalog = DatabaseName; User ID = UserName; Password = Password"
sql = "Your SQL Statement Here , like Select * from product"
You have to replace the string with your realtime variables.