dataset1.vb

Visual Basic.NET应用编程150例

        
        Friend ReadOnly Property PhotoColumn As DataColumn
            Get
                Return Me.columnPhoto
            End Get
        End Property
        
        Friend ReadOnly Property NotesColumn As DataColumn
            Get
                Return Me.columnNotes
            End Get
        End Property
        
        Friend ReadOnly Property ReportsToColumn As DataColumn
            Get
                Return Me.columnReportsTo
            End Get
        End Property
        
        Friend ReadOnly Property PhotoPathColumn As DataColumn
            Get
                Return Me.columnPhotoPath
            End Get
        End Property
        
        Public Default ReadOnly Property Item(ByVal index As Integer) As EmployeesRow
            Get
                Return CType(Me.Rows(index),EmployeesRow)
            End Get
        End Property
        
        Public Event EmployeesRowChanged As EmployeesRowChangeEventHandler
        
        Public Event EmployeesRowChanging As EmployeesRowChangeEventHandler
        
        Public Event EmployeesRowDeleted As EmployeesRowChangeEventHandler
        
        Public Event EmployeesRowDeleting As EmployeesRowChangeEventHandler
        
        Public Overloads Sub AddEmployeesRow(ByVal row As EmployeesRow)
            Me.Rows.Add(row)
        End Sub
        
        Public Overloads Function AddEmployeesRow( _
                    ByVal LastName As String,  _
                    ByVal FirstName As String,  _
                    ByVal Title As String,  _
                    ByVal TitleOfCourtesy As String,  _
                    ByVal BirthDate As Date,  _
                    ByVal HireDate As Date,  _
                    ByVal Address As String,  _
                    ByVal City As String,  _
                    ByVal _Region As String,  _
                    ByVal PostalCode As String,  _
                    ByVal Country As String,  _
                    ByVal HomePhone As String,  _
                    ByVal Extension As String,  _
                    ByVal Photo() As Byte,  _
                    ByVal Notes As String,  _
                    ByVal ReportsTo As Integer,  _
                    ByVal PhotoPath As String) As EmployeesRow
            Dim rowEmployeesRow As EmployeesRow = CType(Me.NewRow,EmployeesRow)
            rowEmployeesRow.ItemArray = New Object() {Nothing, LastName, FirstName, Title, TitleOfCourtesy, BirthDate, HireDate, Address, City, _Region, PostalCode, Country, HomePhone, Extension, Photo, Notes, ReportsTo, PhotoPath}
            Me.Rows.Add(rowEmployeesRow)
            Return rowEmployeesRow
        End Function
        
        Public Function FindByEmployeeID(ByVal EmployeeID As Integer) As EmployeesRow
            Return CType(Me.Rows.Find(New Object() {EmployeeID}),EmployeesRow)
        End Function
        
        Public Function GetEnumerator() As System.Collections.IEnumerator Implements System.Collections.IEnumerable.GetEnumerator
            Return Me.Rows.GetEnumerator
        End Function
        
        Public Overrides Function Clone() As DataTable
            Dim cln As EmployeesDataTable = CType(MyBase.Clone,EmployeesDataTable)
            cln.InitVars
            Return cln
        End Function
        
        Protected Overrides Function CreateInstance() As DataTable
            Return New EmployeesDataTable
        End Function
        
        Friend Sub InitVars()
            Me.columnEmployeeID = Me.Columns("EmployeeID")
            Me.columnLastName = Me.Columns("LastName")
            Me.columnFirstName = Me.Columns("FirstName")
            Me.columnTitle = Me.Columns("Title")
            Me.columnTitleOfCourtesy = Me.Columns("TitleOfCourtesy")
            Me.columnBirthDate = Me.Columns("BirthDate")
            Me.columnHireDate = Me.Columns("HireDate")
            Me.columnAddress = Me.Columns("Address")
            Me.columnCity = Me.Columns("City")
            Me.column_Region = Me.Columns("Region")
            Me.columnPostalCode = Me.Columns("PostalCode")
            Me.columnCountry = Me.Columns("Country")
            Me.columnHomePhone = Me.Columns("HomePhone")
            Me.columnExtension = Me.Columns("Extension")
            Me.columnPhoto = Me.Columns("Photo")
            Me.columnNotes = Me.Columns("Notes")
            Me.columnReportsTo = Me.Columns("ReportsTo")
            Me.columnPhotoPath = Me.Columns("PhotoPath")
        End Sub
        
        Private Sub InitClass()
            Me.columnEmployeeID = New DataColumn("EmployeeID", GetType(System.Int32), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnEmployeeID)
            Me.columnLastName = New DataColumn("LastName", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnLastName)
            Me.columnFirstName = New DataColumn("FirstName", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnFirstName)
            Me.columnTitle = New DataColumn("Title", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnTitle)
            Me.columnTitleOfCourtesy = New DataColumn("TitleOfCourtesy", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnTitleOfCourtesy)
            Me.columnBirthDate = New DataColumn("BirthDate", GetType(System.DateTime), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnBirthDate)
            Me.columnHireDate = New DataColumn("HireDate", GetType(System.DateTime), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnHireDate)
            Me.columnAddress = New DataColumn("Address", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnAddress)
            Me.columnCity = New DataColumn("City", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnCity)
            Me.column_Region = New DataColumn("Region", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.column_Region)
            Me.columnPostalCode = New DataColumn("PostalCode", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnPostalCode)
            Me.columnCountry = New DataColumn("Country", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnCountry)
            Me.columnHomePhone = New DataColumn("HomePhone", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnHomePhone)
            Me.columnExtension = New DataColumn("Extension", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnExtension)
            Me.columnPhoto = New DataColumn("Photo", GetType(System.Byte()), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnPhoto)
            Me.columnNotes = New DataColumn("Notes", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnNotes)
            Me.columnReportsTo = New DataColumn("ReportsTo", GetType(System.Int32), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnReportsTo)
            Me.columnPhotoPath = New DataColumn("PhotoPath", GetType(System.String), Nothing, System.Data.MappingType.Element)
            Me.Columns.Add(Me.columnPhotoPath)
            Me.Constraints.Add(New UniqueConstraint("Constraint1", New DataColumn() {Me.columnEmployeeID}, true))
            Me.columnEmployeeID.AutoIncrement = true
            Me.columnEmployeeID.AllowDBNull = false
            Me.columnEmployeeID.ReadOnly = true
            Me.columnEmployeeID.Unique = true
            Me.columnLastName.AllowDBNull = false
            Me.columnFirstName.AllowDBNull = false
        End Sub
        
        Public Function NewEmployeesRow() As EmployeesRow
            Return CType(Me.NewRow,EmployeesRow)
        End Function
        
        Protected Overrides Function NewRowFromBuilder(ByVal builder As DataRowBuilder) As DataRow
            Return New EmployeesRow(builder)
        End Function
        
        Protected Overrides Function GetRowType() As System.Type
            Return GetType(EmployeesRow)
        End Function
        
        Protected Overrides Sub OnRowChanged(ByVal e As DataRowChangeEventArgs)
            MyBase.OnRowChanged(e)
            If (Not (Me.EmployeesRowChangedEvent) Is Nothing) Then
                RaiseEvent EmployeesRowChanged(Me, New EmployeesRowChangeEvent(CType(e.Row,EmployeesRow), e.Action))
            End If
        End Sub
        
        Protected Overrides Sub OnRowChanging(ByVal e As DataRowChangeEventArgs)
            MyBase.OnRowChanging(e)
            If (Not (Me.EmployeesRowChangingEvent) Is Nothing) Then
                RaiseEvent EmployeesRowChanging(Me, New EmployeesRowChangeEvent(CType(e.Row,EmployeesRow), e.Action))
            End If
        End Sub
        
        Protected Overrides Sub OnRowDeleted(ByVal e As DataRowChangeEventArgs)
            MyBase.OnRowDeleted(e)
            If (Not (Me.EmployeesRowDeletedEvent) Is Nothing) Then
                RaiseEvent EmployeesRowDeleted(Me, New EmployeesRowChangeEvent(CType(e.Row,EmployeesRow), e.Action))
            End If
        End Sub
        
        Protected Overrides Sub OnRowDeleting(ByVal e As DataRowChangeEventArgs)
            MyBase.OnRowDeleting(e)
            If (Not (Me.EmployeesRowDeletingEvent) Is Nothing) Then
                RaiseEvent EmployeesRowDeleting(Me, New EmployeesRowChangeEvent(CType(e.Row,EmployeesRow), e.Action))
            End If
        End Sub
        
        Public Sub RemoveEmployeesRow(ByVal row As EmployeesRow)
            Me.Rows.Remove(row)
        End Sub
    End Class
    
    <System.Diagnostics.DebuggerStepThrough()>  _
    Public Class EmployeesRow
        Inherits DataRow
        
        Private tableEmployees As EmployeesDataTable
        
        Friend Sub New(ByVal rb As DataRowBuilder)
            MyBase.New(rb)
            Me.tableEmployees = CType(Me.Table,EmployeesDataTable)
        End Sub
        
        Public Property EmployeeID As Integer
            Get
                Return CType(Me(Me.tableEmployees.EmployeeIDColumn),Integer)
            End Get
            Set
                Me(Me.tableEmployees.EmployeeIDColumn) = value
            End Set
        End Property
        
        Public Property LastName As String
            Get
                Return CType(Me(Me.tableEmployees.LastNameColumn),String)
            End Get
            Set
                Me(Me.tableEmployees.LastNameColumn) = value
            End Set
        End Property
        
        Public Property FirstName As String
            Get
                Return CType(Me(Me.tableEmployees.FirstNameColumn),String)
            End Get
            Set
                Me(Me.tableEmployees.FirstNameColumn) = value
            End Set
        End Property
        
        Public Property Title As String
            Get
                Try 
                    Return CType(Me(Me.tableEmployees.TitleColumn),String)
                Catch e As InvalidCastException
                    Throw New StrongTypingException("无法获取值，因为它是 DBNull。", e)
                End Try
            End Get
            Set
                Me(Me.tableEmployees.TitleColumn) = value
            End Set
        End Property
        
        Public Property TitleOfCourtesy As String
            Get
                Try 
                    Return CType(Me(Me.tableEmployees.TitleOfCourtesyColumn),String)
                Catch e As InvalidCastException
                    Throw New StrongTypingException("无法获取值，因为它是 DBNull。", e)
                End Try
            End Get
            Set
                Me(Me.tableEmployees.TitleOfCourtesyColumn) = value
            End Set
        End Property
        
        Public Property BirthDate As Date
            Get
                Try 
                    Return CType(Me(Me.tableEmployees.BirthDateColumn),Date)
                Catch e As InvalidCastException
                    Throw New StrongTypingException("无法获取值，因为它是 DBNull。", e)
                End Try
            End Get
            Set
                Me(Me.tableEmployees.BirthDateColumn) = value
            End Set
        End Property
        
        Public Property HireDate As Date
            Get
                Try 
                    Return CType(Me(Me.tableEmployees.HireDateColumn),Date)
                Catch e As InvalidCastException
                    Throw New StrongTypingException("无法获取值，因为它是 DBNull。", e)
                End Try
            End Get
            Set
                Me(Me.tableEmployees.HireDateColumn) = value
            End Set
        End Property
        
        Public Property Address As String
            Get
                Try