I am new to C# and SQL Server 2014 Express and I am using Windows forms.
I am building the small application which read/write from/to SQL Server database.
I am trying to automatically attach SQL Server database, then read data from a table named Test_Table and then fill a Datagridview.
The code I used:
SqlConnection MyConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
SqlCommand MyCommand= new SqlCommand();
DataTable DataTable = new DataTable();
SqlDataAdapter Sql_Data_Adapter= new SqlDataAdapter();
private void button1_Click(object sender, EventArgs e)
{
MyConnection.Open();
MyCommand.CommandText = "SELECT * FROM Test_Table ";
MyCommand.Connection = MyConnection;
Sql_Data_Adapter.SelectCommand = MyCommand;
Sql_Data_Adapter.Fill(DataTable);
dataGridView1.DataSource = DataTable;
MyCommand.Parameters.Clear();
Sql_Data_Adapter.Dispose();
MyConnection.Close();
}
App.config:
<connectionStrings>
<add name="MyConnectionString"
connectionString="Data Source=localhost; AttachDbFilename=D:\\DB\\MyDB.mdf;Integrated Security=True"/>
</connectionStrings>
When I click on button1 it throws an error:
An attempt to attach an auto-named database for file D:\DB\MyDB.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
I have no other databases attached and the database path is correct. I had a look here, here and here but non of them helped.
Any idea how can I automatically attach a SQL Server database file? Thank you
