form1.vb

vb 应用实例 简单应用 ddddddddddddddddddddddddddddddddd

Imports System.Data.SqlClient

Public Class Form1
    Inherits System.Windows.Forms.Form

#Region " Windows Form 设计工具产生的程序代码 "

    Public Sub New()
        MyBase.New()

        '此呼叫为 Windows Form 设计工具的必要项。
        InitializeComponent()

        '在 InitializeComponent() 呼叫之后加入所有的初始设定

    End Sub

    'Form 覆写 Dispose 以清除组件清单。
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    '为 Windows Form 设计工具的必要项
    Private components As System.ComponentModel.IContainer

    '注意: 以下为 Windows Form 设计工具所需的程序
    '您可以使用 Windows Form 设计工具进行修改。
    '请勿使用程序代码编辑器来修改这些程序。
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents Button2 As System.Windows.Forms.Button
    Friend WithEvents DataGrid1 As System.Windows.Forms.DataGrid
    Friend WithEvents Label2 As System.Windows.Forms.Label
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button
        Me.TextBox1 = New System.Windows.Forms.TextBox
        Me.Label1 = New System.Windows.Forms.Label
        Me.Button2 = New System.Windows.Forms.Button
        Me.DataGrid1 = New System.Windows.Forms.DataGrid
        Me.Label2 = New System.Windows.Forms.Label
        CType(Me.DataGrid1, System.ComponentModel.ISupportInitialize).BeginInit()
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(20, 16)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(96, 24)
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "载入"
        '
        'TextBox1
        '
        Me.TextBox1.Location = New System.Drawing.Point(236, 48)
        Me.TextBox1.Name = "TextBox1"
        Me.TextBox1.Size = New System.Drawing.Size(102, 21)
        Me.TextBox1.TabIndex = 1
        Me.TextBox1.Text = "a"
        '
        'Label1
        '
        Me.Label1.AutoSize = True
        Me.Label1.Location = New System.Drawing.Point(20, 56)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(159, 17)
        Me.Label1.TabIndex = 2
        Me.Label1.Text = "过滤ProductName字首的产品"
        '
        'Button2
        '
        Me.Button2.Enabled = False
        Me.Button2.Location = New System.Drawing.Point(369, 48)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New System.Drawing.Size(96, 24)
        Me.Button2.TabIndex = 3
        Me.Button2.Text = "过滤"
        '
        'DataGrid1
        '
        Me.DataGrid1.DataMember = ""
        Me.DataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText
        Me.DataGrid1.Location = New System.Drawing.Point(20, 80)
        Me.DataGrid1.Name = "DataGrid1"
        Me.DataGrid1.Size = New System.Drawing.Size(451, 208)
        Me.DataGrid1.TabIndex = 4
        '
        'Label2
        '
        Me.Label2.AutoSize = True
        Me.Label2.Location = New System.Drawing.Point(133, 24)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(140, 17)
        Me.Label2.TabIndex = 5
        Me.Label2.Text = "按DataGrid的列可以排序"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(491, 302)
        Me.Controls.Add(Me.Label2)
        Me.Controls.Add(Me.DataGrid1)
        Me.Controls.Add(Me.Button2)
        Me.Controls.Add(Me.Label1)
        Me.Controls.Add(Me.TextBox1)
        Me.Controls.Add(Me.Button1)
        Me.Name = "Form1"
        Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
        Me.Text = "DataGrid Filter"
        CType(Me.DataGrid1, System.ComponentModel.ISupportInitialize).EndInit()
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        BindDataGrid()
        '按 DataGrid 的字段可做排序

        Button2.Enabled = True
    End Sub

    Private ds As DataSet

    Private Sub BindDataGrid()
        'SQL Server
        'Dim conn As New SqlConnection("Server=localhost;DataBase=northwind;Integrated Security=SSPI")
        'MSDE
        Dim conn As New SqlConnection("Server=(local);DataBase=northwind;Integrated Security=SSPI")


        Dim da As SqlDataAdapter

        Try
            'da = New SqlDataAdapter("SELECT *  FROM Products", conn)
            Dim cmd1 As New SqlCommand("SELECT *  FROM Products", conn)
            da = New SqlDataAdapter(cmd1)

            ds = New DataSet()
            da.Fill(ds, "Products")
            DataGrid1.DataSource = ds.Tables(0)

        Catch e1 As Exception
            MsgBox("无法读取. " & e1.ToString)
        Finally
            If (conn.State = ConnectionState.Open) Then
                conn.Close()
            End If
        End Try
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        '过滤 ProductName 前缀的产品
        ds.Tables("Products").DefaultView.RowFilter = "ProductName like '" & TextBox1.Text & "%'"

        '未找到
        If ds.Tables("Products").DefaultView.Count = 0 Then
            MessageBox.Show("未找到", "过滤", MessageBoxButtons.OK, MessageBoxIcon.Information)
        End If

        DataGrid1.DataSource = ds.Tables("Products").DefaultView
    End Sub


    Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click

    End Sub
End Class