How to Efficiently Store and Retrieve Images in a MySQL Database?

Storing and Retrieving Images in a Database

Introduction

This article addresses the challenge of storing and retrieving images from a database. The initial code provided encountered issues, prompting a deeper examination and a successful resolution.

Saving Images to the Database

The code snippet demonstrates how to save an image from a PictureBox (PbPicture) to a MySQL database:

    Dim filename As String = txtName.Text + ".jpg"
    Dim FileSize As UInt32

    conn.Close()

    Dim mstream As New System.IO.MemoryStream()
    PbPicture.Image.Save(mstream, System.Drawing.Imaging.ImageFormat.Jpeg)
    Dim arrImage() As Byte = mstream.GetBuffer()

    FileSize = mstream.Length
    Dim sqlcmd As New MySqlCommand
    Dim sql As String = "insert into [your table]  (picture, filename, filesize) " & _
                           "VALUES(@File, @FileName, @FileSize)"

    Try
        conn.Open()
        With sqlcmd
            .CommandText = sql
            .Connection = conn
            .Parameters.AddWithValue("@FileName", filename)
            .Parameters.AddWithValue("@FileSize", FileSize)
            .Parameters.AddWithValue("@File", arrImage)

            .ExecuteNonQuery()
        End With
    Catch ex As Exception
        MsgBox(ex.Message)
    Finally
        conn.Close()
    End Try

Retrieving Images from the Database

To retrieve an image from the database and display it in a PictureBox (PbPicture), follow these steps:

    Dim adapter As New MySqlDataAdapter
    adapter.SelectCommand = Cmd

    data = New DataTable

    adapter = New MySqlDataAdapter("select picture from [yourtable]", conn)

Note: Ensure the query returns only one record since only one PictureBox can display a single image at a time.

    commandbuild = New MySqlCommandBuilder(adapter)
    adapter.Fill(data)

    Dim lb() As Byte = data.Rows(0).Item("picture")
    Dim lstr As New System.IO.MemoryStream(lb)
    PbPicture.Image = Image.FromStream(lstr)
    PbPicture.SizeMode = PictureBoxSizeMode.StretchImage
    lstr.Close()

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