VB.Net - Most "Compact" Query Retrieval

my favorite version :

create a class for connection to db

create a shared method within this class that fills a datatable with the values from the query

  Public Class clsdb
    public Shared Database As String
    public Shared Server As String
    public Shared UserID As String
    public Shared Password As String

    Public Shared Function connectionString() As String
      Dim cs As String
      If _Server Is Nothing Or _UserID Is Nothing Or _Password Is Nothing Or _Database Is Nothing Then
        throw new Exception ("connectionString: incomplete parameters")
      End If
      cs = "SERVER=" + _Server.ToString + ";" ' async=true;"
      cs &= "User ID=" + _UserID.ToString + ";"
      cs &= "Password=" + Trim(_Password.ToString) + ";"
      cs &= "Initial Catalog=" + _Database.ToString + ";"
      cs &= " Connect Timeout=20"
      Return cs
    End Function
    
    Public Shared Function fillDt(ByVal s As String, ByRef dt As DataTable) As Int32
      Dim da As New SqlDataAdapter
      Dim cmd As New SqlCommand
      Dim cnn As New SqlClient.SqlConnection(connectionString())
      Dim nRecord As Int32 = 0
      Try
        cnn.Open()
        cmd.Connection = cnn
        cmd.CommandText = s
        cmd.CommandTimeout = 0
        da.SelectCommand = cmd
        nRecord = da.Fill(dt)
      Catch ex As Exception
        If cnn.State = ConnectionState.Open Then cnn.Close()
        cnn.Dispose()
        Throw New Exception("Error " & ex.Message)
      End Try
      If cnn.State = ConnectionState.Open Then cnn.Close()
      cnn.Dispose()
      Return nRecord
    End Function
  end class 

Select all Open in new window

then just need to initialize the clsdb connection once in the main form

clsdb.Database = "dbname"
clsdb.Server = "192.168.1.xx\sqlservername"
clsdb.userid= "sa"
clsdb.Password = "myserverpass"

then you can populate datatable with :

clsdb.fillDt("SELECT TOP(1) row1, row2)", mydatatable)

Just one line of code