将图像存储在SQL Server数据库中 [英] Store Image in sql server Database

问题描述

我正在尝试使用vb.net和wcf Servics将图像存储在数据库varbinary列中

使用代码

I Am trying to store image in database varbinary Column using vb.net and wcf Servics

Using code

Private Function SaveImage() As Byte()
        Dim arrayImage() As Byte = Nothing
        If (pic_meetPicture.Image Is Nothing) Then
            arrayImage = Nothing
        Else
            Try
                Dim ms As New MemoryStream
                Me.pic_meetPicture.Image.Save(ms, Me.pic_meetPicture.Image.RawFormat)
                arrayImage = ms.GetBuffer
                ms.Close()
                arrayImage = Process.Compressor.UICompressor.Compress(arrayImage)
            Catch ex As Exception
            End Try
        End If
        Return arrayImage
    End Function

Public Shared Function Compress(ByVal buffer As Byte()) As Byte()

            Dim ms As MemoryStream = New MemoryStream()
            Dim zip As GZipStream = New GZipStream(ms, CompressionMode.Compress, True)
            zip.Write(buffer, 0, buffer.Length)
            zip.Close()
            ms.Position = 0

            Dim outStream As MemoryStream = New MemoryStream()
            Dim compressed() As Byte = New Byte(ms.Length) {}
            ms.Read(compressed, 0, compressed.Length)

            Dim gzBuffer() As Byte = New Byte(compressed.Length + 4) {}
            System.Buffer.BlockCopy(compressed, 0, gzBuffer, 4, compressed.Length)
            System.Buffer.BlockCopy(BitConverter.GetBytes(buffer.Length), 0, gzBuffer, 0, 4)
            Return gzBuffer
        End Function

用于显示图像

for display image

Private Sub SetImage(ByVal array As ArrayList)
        Dim arrayImage() As Byte = array(0).Image
        arrayImage = CType(Process.Compressor.UICompressor.Decompress(arrayImage), Byte())
        If arrayImage IsNot Nothing Then
            Dim ms As New MemoryStream(arrayImage)
            pic_meetPicture.Image = Image.FromStream(ms)
            pic_meetPicture.SizeMode = PictureBoxSizeMode.StretchImage
        End If
    End Sub

Public Shared Function Decompress(ByVal gzBuffer As Byte()) As Byte()
            Dim ms As MemoryStream = New MemoryStream()
            Dim msgLength As Integer = BitConverter.ToInt32(gzBuffer, 0)
            ms.Write(gzBuffer, 4, gzBuffer.Length - 4)
            Dim buffer() As Byte = New Byte(msgLength) {}
            ms.Position = 0

            Dim zip As GZipStream = New GZipStream(ms, CompressionMode.Decompress)
            zip.Read(buffer, 0, buffer.Length)

            Return buffer

        End Function

但是当从数据库中获取图像时出现错误有效参数"
请帮助
感谢

But when fetch image from databse then getting error ''parameter in valid''
please Help
thanks

推荐答案

无需查看将数据存储在DB中的代码，我就可以确定问题出在哪里:停止将字符串连接起来以形成ans SQL命令！

请参阅此处:为什么我会得到一个参数无效."从数据库读取图像时出现异常? [

Without looking at your code to store the data in teh DB, I can be pretty sure what the problem is: Stop concatenating strings to form ans SQL command!

See here: Why do I get a "Parameter is not valid." exception when I read an image from my database?[^]

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