How Can I Store and Retrieve Images from a MySQL Database Using Visual Basic?

Storing and Retrieving Images from Database Using C#

Storing and retrieving images from a database blob can be a challenging task, especially when using C#. However, it is crucial to have a reliable solution for applications that require image handling. This article will address this issue by presenting a comprehensive guide to saving and retrieving images from a MySQL database using Visual Basic.

Saving Images to a Database

To store an image in a database, we first need to convert it into a binary format. This can be done using the following code:

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

Next, we create a command to insert the image into the database:

Dim sql = "insert into [your table]  (picture, filename, filesize) VALUES(@File, @FileName, @FileSize)"
Dim sqlcmd As New MySqlCommand
sqlcmd.CommandText = sql
sqlcmd.Connection = conn
sqlcmd.Parameters.AddWithValue("@FileName", filename)
sqlcmd.Parameters.AddWithValue("@FileSize", FileSize)
sqlcmd.Parameters.AddWithValue("@File", arrImage)

Finally, we execute the command to save the image to the database:

sqlcmd.ExecuteNonQuery()

Retrieving Images from a Database

To retrieve an image from the database, we first create a data adapter and a command:

Dim adapter As New MySqlDataAdapter
adapter.SelectCommand = Cmd
data = New DataTable
adapter = New MySqlDataAdapter("select picture from [yourtable]", conn)

Next, we use the data adapter to fill a data table with the image data:

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

Finally, we can extract the image data from the data table and display it in a picture box:

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()

By following these steps, you can effectively store and retrieve images from a database using Visual Basic.

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