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c#pdfsql-server-cefilestreambinaryreader

C# SQL Server CE binary data recovery


I am trying to save and read back pdf files in a SQL Server CE local database. I was able to save them as binary data in an Image column, but I don't know how to read them back and open the pdf file (original format).

Table Schema

Here is how I stored the PDF files:

try
{
    SqlCeConnection con = new SqlCeConnection(@"Data Source = D:\C# Projects\StoreFileSqlCe\StoreFileSqlCe\Test_File_Stotage.sdf");
    con.Open();

    string filePath = textBox1.Text.ToString();
    string filename = Path.GetFileName(filePath);

    FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read);

    BinaryReader br = new BinaryReader(fs);
    Byte[] bytes = br.ReadBytes((Int32)fs.Length);
    br.Close();

    fs.Close();

    string strQuery = "insert into tblFiles(Name, ContentType, Data) values (@Name, @ContentType, @Data)";

    SqlCeCommand cmd = new SqlCeCommand(strQuery, con);
    cmd.Parameters.AddWithValue("@Name", filename);
    cmd.Parameters.AddWithValue("@ContentType", "application/vnd.ms-word");
    cmd.Parameters.AddWithValue("@Data",bytes);

    cmd.ExecuteNonQuery();
}            }
catch (Exception ex)
{
    MessageBox.Show(ex.Message, Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
    con.Close();
    con.Dispose();
}

Solution

  • Try this

                try
                {
    
                    SqlCeConnection con = new SqlCeConnection(@"Data Source = D:\C# Projects\StoreFileSqlCe\StoreFileSqlCe\Test_File_Stotage.sdf");
                    con.Open();
    
                    string strQuery = "select Data where Name = @Name and ContentType = @ContentType";
                    SqlCeCommand cmd = new SqlCeCommand(strQuery, con);
    
                    cmd.Parameters.AddWithValue("@Name", filename);
    
                    cmd.Parameters.AddWithValue("@ContentType", "application/vnd.ms-word");
    
    
                    SqlCeDataReader reader = cmd.ExecuteReader();
                    if (reader != null)
                    {
                        if (reader.Read())
                        {
    
                            byte[] pdf = (byte[])reader["Data"];
                            File.WriteAllBytes(filename, pdf);
    
                        }
                    }
                }
    
    ​