我的老師給了我們示例代碼,它非常類似於下面的代碼。我還沒有收到他的回信,想知道爲什麼我的代碼無法正常工作。有人能給我一些建議,說明我做錯了什麼,或者更簡單的方法來顯示圖像。謝謝你的時間。顯示圖像
<%@ WebHandler Language="VB" Class="images" %>
Imports System
Imports System.Web
Imports System.Data.SqlClient
Public Class images : Implements IHttpHandler
Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
Dim id As String = context.Request.QueryString("ImageId")
Dim userId As Integer = 4
Dim conn As New System.Data.SqlClient.SqlConnection
Dim cmd As New System.Data.SqlClient.SqlCommand
conn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
cmd.Connection = conn
cmd.CommandText = "SELECT Image FROM mrg_Image WHERE [email protected]"
cmd.Parameters.AddWithValue("@userId", userId)
conn.Open()
Dim file_bytes As Byte() = cmd.ExecuteScalar()
Dim file_bytes_stream As New System.IO.MemoryStream(file_bytes)
'During the build - The next line of code is highlighted green with the error message of, "Parameter is invalid"
Dim the_image As New System.Drawing.Bitmap(file_bytes_stream)
context.Response.ContentType = "image/jpg"
the_image.Save(context.Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg)
conn.Close()
End Sub
Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
Get
Return False
End Get
End Property
End Class
它建立在我的機器上細 – 2010-09-21 21:46:10