databusiness.vb

《ASP.NET C#程序设计案例教程》

'********************************************************************************
'这是业务逻辑组件的源文件，主要用于通过数据访问组件和数据库打交道,其中定义了1个类。
'********************************************************************************
Imports System
Imports System.Data
Imports System.Configuration										'因为用到了ConfigurationSettings类
Imports System.DateTime
Imports System.Web
Imports Microsoft.VisualBasic


NameSpace nsShop													'nsShop为自己定义的名称空间的名称

Public Class DataBusiness											'DataBusiness是自己定义的类的名称

	'该函数用来添加新书
	Public Function InsertBook(strBookName As String,strBookAuthor As String,sglBookPrice As Single,intBookNum As Integer,bytPicture() As Byte,strBookIntro As String, strBookIndex As String,intKindId As Integer) As Boolean
		'下面定义一个错误对象，以便捕获错误。
		Dim Exp As Exception
		Try
			'下面设置有关变量值
			Dim dtmSubmitDate As Date=Now()

			'下面建立DataBooks对象，然后调用方法添加数据
			Dim dbks As New DataBooks()
			dbks.InsertBook(strBookName,strBookAuthor,sglBookPrice,intBookNum,bytPicture,strBookIntro, strBookIndex,intKindId,dtmSubmitDate)

			Return(True)
		Catch Exp 
			'如果发生错误
			Return(False)
		End Try
	End Function

	'该函数用来更新一本书的信息
	Public Function UpdateBook(intBookId As Integer,strBookName As String,strBookAuthor As String,sglBookPrice As Single,intBookNum As Integer,bytPicture() As Byte,strBookIntro As String, strBookIndex As String,intKindId As Integer) As Boolean
		'下面定义一个错误对象，以便捕获错误。
		Dim Exp As Exception
		Try
			'下面设置有关变量值
			Dim dtmSubmitDate As Date=Now()

			'下面建立DataBooks对象，然后调用方法添加数据
			Dim dbks As New DataBooks()
			dbks.UpdateBook(intBookId,strBookName,strBookAuthor,sglBookPrice,intBookNum,bytPicture,strBookIntro, strBookIndex,intKindId,dtmSubmitDate)

			Return(True)
		Catch Exp 
			'如果发生错误
			Return(False)
		End Try
	End Function


	'该函数用来删除书
	Public Function DeleteBook(intBookId As integer) As Boolean
		'下面定义一个错误对象，以便捕获错误。
		Dim Exp As Exception
		Try
			'下面建立DataBooks对象，然后调用方法删除数据
			Dim dbks As New DataBooks()
			dbks.DeleteBook(intBookId)

			Return(True)
		Catch exp
			Return(False)
		End Try
	End Function

	'下面查询记录，返回所有指定条件的书籍
	Public Function GetBook(intKindId As integer,strKeyword As String,strkeyField As String) As DataView
		'下面返回DataView对象
		Dim dbks As New DataBooks()
		Dim dv As DataView=dbks.GetBook()													'返回所有书籍

		'下面设置筛选条件，首先设置类别条件
		Dim strFilter As String
		strFilter="BookId>0"																'这个条件其实没有用，主要是为了后面书写其他条件时方便
		If intKindId>0 Then
			strFilter &= " And KindId=" & intKindId	
		End If

		'然后根据查询关键字设置条件
		If strKeyword<>"" And strKeyword<>"全部" Then
			Dim arryKeyword() As String
			Dim I As Integer
			arryKeyword=Split(strKeyword," ")												'按空格拆分多个关键词
			'根据不同的字段进行不同的搜索方式
			If strKeyField="BookName" Then
				For I=0 To arryKeyword.Length-1
					strFilter &= " And " & strkeyField & " Like '%" & arryKeyword(I) & "%'"	'注意And前留一个空格
				Next
			Elseif strkeyField="BookAuthor" Then
				For I=0 To arryKeyword.Length-1
					strFilter &= " And " & strkeyField & " = '" & arryKeyword(I) & "'"		'注意And前留一个空格
				Next
			End If
		End If
		dv.RowFilter = strFilter															'设置筛选条件


		'下面根据排序字段设置排序效果，为了简单，直接按SubmitDate降序排列
		dv.Sort="SubmitDate Desc"														
		'最后返回筛选后的DataView
		Return(dv)
	End Function

	'下面查询记录，返回所有书。注意和上面的函数名称相同，但参数不同
	Public Function GetBook()
		'下面返回DataView对象
		Dim dbks As New DataBooks()
		Dim dv As DataView=dbks.GetBook()													'返回所有书籍
		dv.Sort="SubmitDate Desc"
		Return(dv)
	End Function

	'下面查询记录，返回一本书
	Public Function GetOneBook(intBookId As integer) As DataView
		Dim dbks As New DataBooks()
		Dim dv As DataView=dbks.GetOneBook(intBookId)
		Return(dv)
	End Function

	'下面查询记录，返回某类书销量前10名
	Public Function GetTop10(intKindId As integer) As DataView
		Dim dbks As New DataBooks()
		Dim dv As DataView=dbks.GetTop10(intKindId)
		Return(dv)
	End Function


	'该函数返回所有类别
	Public Function GetKind() As DataView
		Dim dks As New DataKinds()
		Dim dv As DataView=dks.GetKind()
		dv.Sort="KindId"																	'设置排序条件
		Return(dv)
	End Function

	'删除类别
	Public Sub DeleteKind(intKindId As Integer)
		Dim dks As New DataKinds()
		dks.DeleteKind(intKindId)
	End Sub

	'更新类别信息
	Public Sub UpdateKind(intKindId As Integer,strKindName as String)
		Dim dks As New DataKinds()
		dks.UpdateKind(intKindId,strKindName)
	End Sub

	'添加类别
	Public Sub InsertKind(strKindName as String)
		Dim dks As New DataKinds()
		dks.InsertKind(strKindName)
	End Sub

	'该函数用于返回所有订单
	Public Function GetOrder()
		'下面返回DataView对象
		Dim dos As New DataOrders()
		Dim dv As DataView=dos.GetOrder()													'返回所有书籍
		dv.Sort="Consign,SubmitDate Desc"												'按是否已经发货和提交日期排序
		Return(dv)
	End Function

	'删除订单
	Public Sub DeleteOrder(intOrderId As Integer)
		Dim dos As New DataOrders()
		dos.DeleteOrder(intOrderId)
	End Sub

	'更新订单
	Public Sub UpdateOrder(intOrderId As Integer)
		Dim dos As New DataOrders()
		dos.UpdateOrder(intOrderId,Now())
	End Sub

End Class
End NameSpace