概述
----------单层体系结构
<%@ Page Language="vb" %><%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<HTML>
<HEAD>
<script runat=server>
Public Sub Page_Load(sender As Object, e As EventArgs)
Dim strImageID as String = Request.QueryString("id")
Dim myConnection As New SqlConnection("Data Source=.;Initial Catalog=mxh;User Id=sa;Password=;")
Dim myCommand As New SqlCommand("Select PersonImageType, PersonImage from Person Where PersonID=" _
+ strImageID, myConnection)
Try
myConnection.Open()
Dim myDataReader as SqlDataReader
myDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection)
Do While (myDataReader.Read())
Response.ContentType = myDataReader.Item("PersonImageType")
Response.BinaryWrite(myDataReader.Item("PersonImage"))
Loop
myConnection.Close()
Catch SQLexc As SqlException
End Try
End Sub
</script>
</HEAD>
<body>
<form runat="server" ID="Form1"></form>
</body></HTML>
----------三层体系结构
---界面层
<%@ Page Language="vb" AutoEventWireup="false" Codebehind="ReadImage.aspx.vb" Inherits="ShopGoByGo.WebModules.Product.Web.ReadImage" %>
<HTML>
<HEAD>
</HEAD>
<body><form runat="server" ID="Form1">
<FONT face="宋体"></FONT>
</form></body></HTML>
---表示层
Public Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim productImagesClass As New ProductBusiness.Product(Request.QueryString("id"))
Dim myDataReader As SqlDataReader = productImagesClass.GetProductImage()
Do While (myDataReader.Read())
Response.BinaryWrite(myDataReader.Item("ProductPicture"))
Loop
End Sub
---业务层
#Region "返回指定产品的产品Product_First表里的图片"
Public Function GetProductImage() As SqlDataReader
Dim theProduct As New Data.Product(mySettings.ConnectionString)
Return theProduct.GetProductImage(myProductId)
End Function
#End Region
---数据层
#Region "根据指定的ProductID返回产品的图片"
Public Function GetProductImage(ByVal productId As Integer) As SqlDataReader
' 创建参数
Dim parameters As SqlParameter() = { _
New SqlParameter("@ProductId", SqlDbType.Int, 4)}
parameters(0).Value = productId
Dim products As SqlDataReader
Try
products = Me.ExecuteReader(ConnectionString, CommandType.StoredProcedure, "sp_Product_GetProductImage", parameters)
Return products
Finally
End Try
End Function
#End Region
---存储过程
ALTER PROCEDURE sp_Product_GetProductImage
@ProductID int
AS
Select ProductPicture from Product_First Where ProductID=@ProductID
RETURN
转载于:https://www.cnblogs.com/xzcastle/archive/2006/01/17/319105.html
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