怎样读取oracle数据库中的blob字段并显示在Image上 - 编程论坛

#2

zhlxh12012007-09-11 16:53

Dim strConnection As String = System.Configuration.ConfigurationManager.AppSettings("kksb")
Dim Conn As System.Data.OleDb.OleDbConnection = New System.Data.OleDb.OleDbConnection(strConnection)
Dim strSQL As String = "select photo from t_veh_matching where picname=" & Request("picname")
Dim comm As System.Data.OleDb.OleDbCommand = New System.Data.OleDb.OleDbCommand(strSQL, Conn)
Dim myReader As System.Data.OleDb.OleDbDataReader = comm.ExecuteReader(CommandBehavior.SequentialAccess)
Do While myReader.Read()
' Get the publisher id, which must occur before getting the logo.
Photo = myReader.GetString(0)
以上是我的程序
红色一句报错：指定的转换无效

#3

bygg2007-09-11 19:12

你的Photo是什么类型啊?
myReader.GetString(0) 这个取出来是string型的

#4

zhlxh12012007-09-12 08:45

是blob类型的

#5

zhlxh12012007-09-12 08:46

我是不是改用GetByte来取值

#6

bygg2007-09-12 10:20

是的,你试试吧
 https://bbs.bc-cn.net/viewthread.php?tid=112678&star=at#

#7

zhlxh12012007-09-12 12:34

我使用BS方式编写的
程序代码与你给的有点出入
由于我是新手
请指点

#8

zhlxh12012007-09-12 15:54

Dim strConnection As String = System.Configuration.ConfigurationManager.AppSettings("kksb")
Dim Conn As System.Data.OleDb.OleDbConnection = New System.Data.OleDb.OleDbConnection(strConnection)
Dim strSQL As String = "select photo from t_veh_matching where picname=" & Request("picname")
Dim comm As System.Data.OleDb.OleDbCommand = New System.Data.OleDb.OleDbCommand(strSQL, Conn)
Dim de As System.Data.OleDb.OleDbDataReader
dr = comm.ExcuteScalar()

#9

bygg2007-09-12 20:08

用DataReader取值..再用BTYE的形式转成Image,

#10

zhlxh12012008-01-15 15:55

？？？

怎么办？

#11

zhlxh12012008-01-18 11:21

???

咋就没人理我呢？

#12

fairy42008-01-18 12:04

人家都給你相似的詳細代碼！還要怎么幫你？？？？？？？？？
按照你的所有詳細要求，幫你完成你的工作？？？？

#13

bygg2008-01-18 12:32

Dim data() As Byte = ds.Tables("employees").Rows(9)("photo")
Dim stmphoto As New MemoryStream(data)
PictureBox1.Image = Image.FromStream(stmphoto)

这是我给的链接网页中的三句，这个你能看懂吧？
那你就成功了。