数据库读取图片出现问题

[zl_157526769]

'将图片导出
Private Sub OpenPhoto()
sqlconnection1.Open()
Dim custDA As New SqlDataAdapter("SELECT * FROM products", sqlconnection1)
Dim myDataset As New DataSet
custDA.Fill(myDataset, "products")
Dim myBytes() As Byte = myDataset.Tables(0).Rows(0).Item("pdPhoto")
Dim myStream As New IO.MemoryStream(myBytes)
Me.PictureBox1.Image = Image.FromStream(myStream, True) '这里发出"使用了无效参数的错误"
sqlconnection1.Close()
End Sub

请大虾帮帮我,为什么是无效参数?

[zxinzhi]

别往Dataset中里写二进制，直接表图片提出给PictureBox1.Image 不就好了

[guopeng_028]

Private Sub DisPic()
''''''''''显不图片的方法'''''''''''''
Dim picstr As String = "select img from tb_img where (imgid=?)"
Dim piccmd As New OleDbCommand(picstr, conn)
piccmd.Connection = conn

piccmd.Parameters.Add(New OleDb.OleDbParameter("imgid", System.Data.OleDb.OleDbType.VarWChar, 50))
piccmd.Parameters("imgid").Value = ID号TB.Text

If piccmd.Connection.State = ConnectionState.Closed Then
Try
piccmd.Connection.Open()
Catch ex As Exception

End Try
End If
Dim dr As OleDbDataReader
dr = piccmd.ExecuteReader()
If dr.Read Then
If Not IsDBNull(dr.Item(0)) Then
Dim bt() As Byte = dr.Item(0)
Dim ms As MemoryStream = New MemoryStream(bt)
PictureBox1.Image = Image.FromStream(ms)
End If
End If
piccmd.Connection.Close()


这是我写的一小部分程序
是用二进制读的
改成C#应该不难吧
自己翻译一下吧

[点点星灯]

--参数就是数据库中对应的数据字段的值

Private Function ShowImageNew(ByVal Userimage() As Byte)
Dim b() As Byte
b = Userimage
If (b.Length > 0) Then
Dim stream As New MemoryStream(b, True)
stream.Write(b, 0, b.Length)
Me.PicMan.Image = New Bitmap(stream)
stream.Close()
End If
End Function

--调用
ShowImageNew(tableUpimage.Rows(0).Item("UserImage")) '显示图片

[zl_157526769]

楼上的基本上和我的一样,我试着用你的方法,但还是一样.发出无效参数的错误.这可能是我的其他语句有错误吧....

[ck_邬]

我当时也遇到过同样问题,
后来发现是我存入的图片时出现了问题,
数据库里存入的图片数据不完整,
再读出来的时候就出现跟你一样的错误了..