Database 从sql server数据库在vb.net中插入和显示图像
我需要上传和显示图像到和从数据库。我已经写了这个上传代码,它上传罚款。除了一个问题。当我没有选择图像时,它崩溃了。有人能帮我修正空值吗?在IE中如何显示图像 插入图像的代码-Database 从sql server数据库在vb.net中插入和显示图像,database,vb.net,image,insert,Database,Vb.net,Image,Insert,我需要上传和显示图像到和从数据库。我已经写了这个上传代码,它上传罚款。除了一个问题。当我没有选择图像时,它崩溃了。有人能帮我修正空值吗?在IE中如何显示图像 插入图像的代码- Dim imageInfo As FileInfo = Nothing Dim data() As Byte = Nothing imageInfo = New FileInfo(Me.UploadLogo.Value.Trim()) Dim imagestream As FileStream = New FileStre
Dim imageInfo As FileInfo = Nothing
Dim data() As Byte = Nothing
imageInfo = New FileInfo(Me.UploadLogo.Value.Trim())
Dim imagestream As FileStream = New FileStream(imageInfo.ToString, FileMode.Open)
if name_id > 0
ReDim data(imagestream.Length - 1)
imagestream.Read(data, 0, imagestream.Length)
imagestream.Close()
Sqlstr = "UPDATE logos WITH(ROWLOCK) " & _
"SET Logo=@Logo,Modified_Date=GETDATE() " & _
"WHERE ID = " + name_id.ToString + ""
Else
Sqlstr = "INSERT logos (Logo,Created_Date) " & _
"VALUES ("@Logo,GETDATE())"
End If
SqlCmd = New SqlCommand(Sqlstr, SqlCnn)
Dim pictureParameter As SqlParameter = Nothing
pictureParameter = New SqlParameter("@Logo", SqlDbType.Image)
pictureParameter.Value = data
SqlCmd.Parameters.Add(pictureParameter)
SqlCmd.ExecuteScalar()
仅当选择图像时,此操作才可以正常工作,因为空值而崩溃。
另外,请帮助我的图像显示。谢谢要解决您的文件未选择问题,您应该有一个If语句,内容如下:
If Not File.Exists(Me.UploadLogo.Value.Trim())
' Exit out or handle no file selected
End If