webform1.aspx.vb

Visual Basic.NET应用编程150例

Public Class WebForm1
    Inherits System.Web.UI.Page
    Protected WithEvents SqlDataAdapter1 As System.Data.SqlClient.SqlDataAdapter
    Protected WithEvents SqlSelectCommand1 As System.Data.SqlClient.SqlCommand
    Protected WithEvents SqlInsertCommand1 As System.Data.SqlClient.SqlCommand
    Protected WithEvents SqlUpdateCommand1 As System.Data.SqlClient.SqlCommand
    Protected WithEvents SqlDeleteCommand1 As System.Data.SqlClient.SqlCommand
    Protected WithEvents SqlConnection1 As System.Data.SqlClient.SqlConnection
    Protected WithEvents DsCategories1 As WebApplication6.dsCategories
    Protected WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid

#Region " Web 窗体设计器生成的代码 "

    '该调用是 Web 窗体设计器所必需的。
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.SqlDataAdapter1 = New System.Data.SqlClient.SqlDataAdapter()
        Me.SqlSelectCommand1 = New System.Data.SqlClient.SqlCommand()
        Me.SqlInsertCommand1 = New System.Data.SqlClient.SqlCommand()
        Me.SqlUpdateCommand1 = New System.Data.SqlClient.SqlCommand()
        Me.SqlDeleteCommand1 = New System.Data.SqlClient.SqlCommand()
        Me.SqlConnection1 = New System.Data.SqlClient.SqlConnection()
        Me.DsCategories1 = New WebApplication6.dsCategories()
        CType(Me.DsCategories1, System.ComponentModel.ISupportInitialize).BeginInit()
        '
        'SqlDataAdapter1
        '
        Me.SqlDataAdapter1.DeleteCommand = Me.SqlDeleteCommand1
        Me.SqlDataAdapter1.InsertCommand = Me.SqlInsertCommand1
        Me.SqlDataAdapter1.SelectCommand = Me.SqlSelectCommand1
        Me.SqlDataAdapter1.TableMappings.AddRange(New System.Data.Common.DataTableMapping() {New System.Data.Common.DataTableMapping("Table", "Categories", New System.Data.Common.DataColumnMapping() {New System.Data.Common.DataColumnMapping("CategoryID", "CategoryID"), New System.Data.Common.DataColumnMapping("CategoryName", "CategoryName"), New System.Data.Common.DataColumnMapping("Description", "Description")})})
        Me.SqlDataAdapter1.UpdateCommand = Me.SqlUpdateCommand1
        '
        'SqlSelectCommand1
        '
        Me.SqlSelectCommand1.CommandText = "SELECT CategoryID, CategoryName, Description FROM Categories"
        Me.SqlSelectCommand1.Connection = Me.SqlConnection1
        '
        'SqlInsertCommand1
        '
        Me.SqlInsertCommand1.CommandText = "INSERT INTO Categories(CategoryName, Description) VALUES (@CategoryName, @Descrip" & _
        "tion); SELECT CategoryID, CategoryName, Description FROM Categories WHERE (Categ" & _
        "oryID = @@IDENTITY)"
        Me.SqlInsertCommand1.Connection = Me.SqlConnection1
        Me.SqlInsertCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@CategoryName", System.Data.SqlDbType.NVarChar, 15, "CategoryName"))
        Me.SqlInsertCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Description", System.Data.SqlDbType.NVarChar, 1073741823, "Description"))
        '
        'SqlUpdateCommand1
        '
        Me.SqlUpdateCommand1.CommandText = "UPDATE Categories SET CategoryName = @CategoryName, Description = @Description WH" & _
        "ERE (CategoryID = @Original_CategoryID) AND (CategoryName = @Original_CategoryNa" & _
        "me); SELECT CategoryID, CategoryName, Description FROM Categories WHERE (Categor" & _
        "yID = @CategoryID)"
        Me.SqlUpdateCommand1.Connection = Me.SqlConnection1
        Me.SqlUpdateCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@CategoryName", System.Data.SqlDbType.NVarChar, 15, "CategoryName"))
        Me.SqlUpdateCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Description", System.Data.SqlDbType.NVarChar, 1073741823, "Description"))
        Me.SqlUpdateCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Original_CategoryID", System.Data.SqlDbType.Int, 4, System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0, Byte), "CategoryID", System.Data.DataRowVersion.Original, Nothing))
        Me.SqlUpdateCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Original_CategoryName", System.Data.SqlDbType.NVarChar, 15, System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0, Byte), "CategoryName", System.Data.DataRowVersion.Original, Nothing))
        Me.SqlUpdateCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@CategoryID", System.Data.SqlDbType.Int, 4, "CategoryID"))
        '
        'SqlDeleteCommand1
        '
        Me.SqlDeleteCommand1.CommandText = "DELETE FROM Categories WHERE (CategoryID = @Original_CategoryID) AND (CategoryNam" & _
        "e = @Original_CategoryName)"
        Me.SqlDeleteCommand1.Connection = Me.SqlConnection1
        Me.SqlDeleteCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Original_CategoryID", System.Data.SqlDbType.Int, 4, System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0, Byte), "CategoryID", System.Data.DataRowVersion.Original, Nothing))
        Me.SqlDeleteCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@Original_CategoryName", System.Data.SqlDbType.NVarChar, 15, System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0, Byte), "CategoryName", System.Data.DataRowVersion.Original, Nothing))
        '
        'SqlConnection1
        '
        Me.SqlConnection1.ConnectionString = "data source=ylm;initial catalog=Northwind;integrated security=SSPI;persist security info=False;workstation id=YLM;packet size=4096"
        '
        'DsCategories1
        '
        Me.DsCategories1.DataSetName = "dsCategories"
        Me.DsCategories1.Locale = New System.Globalization.CultureInfo("fr-BE")
        Me.DsCategories1.Namespace = "http://www.tempuri.org/dsCategories.xsd"
        CType(Me.DsCategories1, System.ComponentModel.ISupportInitialize).EndInit()

    End Sub

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: 此方法调用是 Web 窗体设计器所必需的
        '不要使用代码编辑器修改它。
        InitializeComponent()
    End Sub

#End Region

    Private Sub Page_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load
        SqlDataAdapter1.Fill(DsCategories1)
        If Not IsPostBack Then
            DataGrid1.DataBind()
        End If

    End Sub

    Private Sub DataGrid1_EditCommand(ByVal source As Object, _
    ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) _
    Handles DataGrid1.EditCommand
        DataGrid1.EditItemIndex = e.Item.ItemIndex
        DataGrid1.DataBind()

    End Sub

    Private Sub DataGrid1_CancelCommand(ByVal source As Object, _
    ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) _
    Handles DataGrid1.CancelCommand
        DataGrid1.EditItemIndex = -1
        DataGrid1.DataBind()
    End Sub

    Private Sub DataGrid1_UpdateCommand(ByVal source As Object, _
    ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) _
    Handles DataGrid1.UpdateCommand
        Dim key As String = DataGrid1.DataKeys(e.Item.ItemIndex).ToString()
        '获取当前行的数据键即categoryID字段的值
        Dim categoryName, categoryDescription As String
        Dim tb As TextBox
        tb = CType(e.Item.Cells(2).Controls(0), TextBox)
        categoryName = tb.Text
        '获取在DataGrid1中当前行的CategoryName列的值并存储到变量中

        tb = CType(e.Item.Cells(3).Controls(0), TextBox)
        categoryDescription = tb.Text
        '获取在DataGrid1中当前行的Description列的值并存储到变量中

        Dim r As dsCategories.CategoriesRow
        r = DsCategories1.Categories.FindByCategoryID(key)
        '通过数据键的值定位行并返回一个对该行的引用r
        r.CategoryName = categoryName
        r.Description = categoryDescription
        '更新当前行
        SqlDataAdapter1.Update(DsCategories1)
        '将更改从数据集发送到数据库
        DataGrid1.DataBind()

        DataGrid1.EditItemIndex = -1
        DataGrid1.DataBind()
        '将网格中的当前行切换出编辑模式
    End Sub
End Class