vb.net - 如何将数据库中的图像添加到PictureBox？

Question

我正在使用它从数据库获取图像字节

cmd.CommandText = "select imagedate from projectimages where imagename = '" + _
    ListBox1.Text + "' and CSVprojectref=checksum('" + textboxFileRef.Text + "')"

Dim img As Object = cmd.ExecuteScalar()

现在如何将其添加到 PictureBox.image。我在检索图像并将其显示在 PictureBox 中时遇到很多麻烦。

数据类型是sql数据库中的图像，我使用此代码将图像保存到数据库

         Dim ms As New IO.MemoryStream

        If imageFilename.Contains("jpeg") Or imageFilename.Contains("jpg") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg)

        End If
        If imageFilename.Contains("png") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Png)
        End If
        If imageFilename.Contains("gif") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Gif)
        End If
        If imageFilename.Contains("bmp") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp)
        End If

        Dim bytes() As Byte = ms.ToArray
        Dim img As String = Convert.ToBase64String(bytes)


        Dim cmd As New OleDb.OleDbCommand("insert projectimages values('" + imageNameTemp + "','" + img + "',CHECKSUM('" + textboxFileRef.Text + "'))", con)
        cmd.ExecuteNonQuery()

Answer 1

经过 5-6 小时搜索论坛和博客以及我喜欢的所有内容后...将图像保存到数据库

1-数据类型应该是数据库中的图像

现在将图像存储到sql数据库时添加此代码

    OpenFileDialog1.ShowDialog()
    imageFilename = OpenFileDialog1.FileName
    Dim imageUpload As Image
    imageUpload = Image.FromFile(OpenFileDialog1.FileName)



    If imageFilename <> "" Then

        Dim imageNameTemp As String

        imageNameTemp = imageFilename

        While (imageNameTemp.Contains("\"))


            imageNameTemp = imageNameTemp.Remove(0, imageNameTemp.IndexOf("\") + 1)
        End While

        Dim ms As New IO.MemoryStream

        If imageFilename.Contains("jpeg") Or imageFilename.Contains("jpg") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg)

        End If
        If imageFilename.Contains("png") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Png)
        End If
        If imageFilename.Contains("gif") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Gif)
        End If
        If imageFilename.Contains("bmp") Then
            imageUpload.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp)
        End If

        'Dim cmd As New SqlCommand("INSERT INTO projectimages (imagename,imagedate,csvprojectref) VALUES ('" + imageFilename + "',@BLOBData,CHECKSUM('" + textboxFileRef.Text + "'))", con)

        Dim b() As Byte = ms.ToArray()

        Dim cmd As New SqlCommand("INSERT INTO projectimages (imagename,imagedate,csvprojectref) VALUES ('" + imageNameTemp + "',@BLOBData,CHECKSUM('" + textboxFileRef.Text + "'))", con)

        cmd.Parameters.Add("@BLOBData", SqlDbType.Image, b.Length).Value = b
        '    Dim cmd As New SqlCommand("insert projectimages(imagename,imagedate,csvprojectref) values('imagma','" + img + "',CHECKSUM('" + textboxFileRef.Text + "'))", con)

        cmd.ExecuteNonQuery()

        '  cmdTemp.Parameters.Add("@photo", SqlDbType.Image, b.Length).Value = b

    End If

何时检索数据以插入到图片框中使用此代码...

  cmd.CommandText = "select imagedate from projectimages where imagename = '" +      ListBox1.Text + "' and CSVprojectref=checksum('" + textboxFileRef.Text + "')"


        cmd.Connection = con
        Dim da As New SqlDataAdapter(cmd)
        Dim ds As New DataSet()
        da.Fill(ds, "projectimages")
        Dim c As Integer = ds.Tables(0).Rows.Count
        If c > 0 Then
            Dim bytBLOBData() As Byte = _
                ds.Tables(0).Rows(c - 1)("imagedate")
            Dim stmBLOBData As New MemoryStream(bytBLOBData)
            PictureBox1.Image = Image.FromStream(stmBLOBData)
        End If