Load/Unload images into/from DB table

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Introduction

We all often need to store Binary Large Objects (BLOBs) into a DB table and then get them from there. Now I'm going to explain the easiest way to do this.

Prepare Database

Run SQL Server Enterprise Manager and create a new database, call it 'Test'. Create a new table and call it Images.

CREATE TABLE Images ([stream] [image] NULL)

That's all you need.

Store Image into DB table

...
byte[] content = ReadBitmap2ByteArray(fileName);
StoreBlob2DataBase(content);
...
protected static byte[] ReadBitmap2ByteArray(string fileName)
{
  using(Bitmap image = new Bitmap(fileName))
  {
    MemoryStream stream = new MemoryStream();
    image.Save(stream, System.Drawing.Imaging.ImageFormat.Bmp);
    return stream.ToArray();
  }
}

protected static void StoreBlob2DataBase(byte[] content)
{
   SqlConnection con = Connection;
   con.Open();
   try
   {
     // insert new entry into table
     SqlCommand insert = new SqlCommand(
     "insert into Images ([stream]) values (@image)",con);
     SqlParameter imageParameter = 
     insert.Parameters.Add("@image", SqlDbType.Binary);
     imageParameter.Value = content;
     imageParameter.Size  = content.Length;
     insert.ExecuteNonQuery();
   }
   finally
   {
      con.Close();
   }
}

Store Images for OLEDB provider

Some of us use OLEDB provider to communicate with SQL Server. In this case you should use the code below to store images into your DB. Pay attention to using '?' instead of '@image' in the SQL query.

protected static void StoreBlob2DataBaseOleDb(byte[] content)
{
   try
   {
      using(OleDbConnection con = Connection)
      {
         con.Open();

         // insert new entry into table
         using(OleDbCommand insert = new OleDbCommand(
             "insert into Images ([stream]) values (?)",con))
         {
            OleDbParameter imageParameter = 
            insert.Parameters.Add("@image", OleDbType.Binary);
            imageParameter.Value = content;
            imageParameter.Size  = content.Length;
            insert.ExecuteNonQuery();
         }
      }
   }
   catch(Exception ex)
   {
      // some exception processing
   }
}

Get Image from DB table and show it

 // get image
 DataRowView drv = (DataRowView) _cm.Current;
 byte[] content = (byte[])drv["stream"];
 MemoryStream stream = new MemoryStream(content);
 Bitmap image = new Bitmap(stream);
 
 ShowImageForm f = new ShowImageForm();
 f._viewer.Image = image;
 f.ShowDialog(this);

Conclusion

You can use this technique to work with any type of binary data without using storage procedures. Good Luck.

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