這篇文章是我寫的"如何把圖片存入sqlServer中"的後續。我建議你在讀這篇文章之前先看看那篇。
和存儲圖片相比，讀取圖片就要簡單多了。輸出一副圖片我們要做的就是使用Response對象的BinaryWrite方法。
同時設置圖片的格式。在這篇文章中，我們將討論如何從SqlServer中檢索圖片。
並將學習以下幾個方面的知識.
·如何設置圖片的格式？
·如何使用BinaryWrite方法。
我們已經在Person表中存儲了數據，那麼我們就寫些代碼來從表中讀取數據。
下面的代碼檢索了所有的值從Person表中。
從sqlserver中讀取圖片的代碼.
Public Sub Page_Load(sender As Object, e As EventArgs)
Dim myConnection As New SqlConnection(ConfigurationSettings.AppSettings("ConnectionString"))
Dim myCommand As New SqlCommand("Select * from Person", 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()
Response.Write("Person info successfully retrieved!")
Catch SQLexc As SqlException
Response.Write("Read Failed : " & SQLexc.ToString())
End Try
End Sub
看看他是怎麼工作的？
上面的例子很簡單。我們所作的就是執行一個sql語句，再循環讀取所有的記錄（looping through all the records）.
在顯示圖片之前，我們先設置了圖片的contentType，然後我們使用BinaryWrite方法把圖片輸出到浏覽器。
源代碼：
/// retriving.aspx
<%@ Page Language="vb" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<HTML>
<HEAD>
<title>Retrieving Image from the Sql Server</title>
<script runat=server>
Public Sub Page_Load(sender As Object, e As EventArgs)
' Create Instance of Connection and Command Object
Dim myConnection As New SqlConnection(ConfigurationSettings.AppSettings("ConnectionString"))
Dim myCommand As New SqlCommand("Select * from Person", 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()
Response.Write("Person info successfully retrieved!")
Catch SQLexc As SqlException
Response.Write("Read Failed : " & SQLexc.ToString())
End Try
End Sub
</script>
</HEAD>
<body style="font: 10pt verdana">
</body>
</HTML>
