connectionstringbuilderdialog.vb

讲解如何实现从数据库同步下载数据以及在窗口上显示数据

Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Text
Imports System.Windows.Forms
Imports System.Data.Common

Public Class ConnectionStringBuilderDialog
    Dim _ConnectionString As String
    Public ReadOnly Property ConnectionString()
        Get
            Return _ConnectionString
        End Get
    End Property

    Dim _ProviderFactory As DbProviderFactory
    Public Function EditConnectionString(ByVal ProviderFactory As DbProviderFactory, ByVal ConnectionStringBuilder As DbConnectionStringBuilder) As DialogResult
        _ConnectionString = ConnectionStringBuilder.ConnectionString
        _ProviderFactory = ProviderFactory

        propGrid.SelectedObject = ConnectionStringBuilder
        Dim retval As DialogResult = Me.ShowDialog()

        If retval = System.Windows.Forms.DialogResult.OK Then
            _ConnectionString = ConnectionStringBuilder.ConnectionString
        End If
        Return retval
    End Function

    Sub btnTest_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnTest.Click
        Try
            Me.Cursor = Cursors.WaitCursor
            Using cn As DbConnection = _ProviderFactory.CreateConnection()
                Dim bldr As DbConnectionStringBuilder = DirectCast(propGrid.SelectedObject, DbConnectionStringBuilder)
                cn.ConnectionString = bldr.ConnectionString
                cn.Open()
            End Using
            Me.Cursor = Cursors.Default
            MessageBox.Show("Success!", "Connection attempt succeeded!", MessageBoxButtons.OK, MessageBoxIcon.Information)
        Catch ex As Exception
            Me.Cursor = Cursors.Default
            MessageBox.Show(ex.Message, "Connection attempt failed!", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try
        Me.Cursor = Cursors.Default
    End Sub
End Class