DatabaseConnect ion Strings

[jonc1]

Can anyone explain how these work in relation to setting and application setting files. I know that application settings can not be modified programatically at runtime, although they can be changed in the XML.
(I did try adding a set method in my settings.cs to allow me to update the application scoped databaseconnect ion string, but VS was not being foole d by that). However, I want to change my DatabaseConnect ion string (to point at a different database), but the property is an application and not a user one.

My objective is simple I'd like the user to be able to open a different sdf (database file) from the one currently in use, and for that to then be saved for next time.

[Bassem]

Hi,
Why didn't hard-code the connection string for a SqlDataSource and modify it using a OpenFileDialog.

[jonc1]

Hi,
Thank you! I did think of that but VS created the connection for me and I assume pointed the DataSet to it. How would\where would I modify my existing connection ? I can't find the SqlServer connection object that VS MUST (I guess) have created?
.

[Bassem]

No instead of drag and drop the SqlDataSource,
create a class that accept either the name of the database or the absolute location of the database, i did some thing like this before.

public class DataClass
{
    private SqlDataSource sqlDataSource;
    public DataClass(string name)
    {
        sqlDataSource = new SqlDataSource();
        sqlDataSource.ConnectionString = @"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\" + name + ";Integrated Security=True;User Instance=True";
    }
 
    public SqlDataSource SqlDataSource
    {
        get { return sqlDataSource; }
    }
}
 

now you can pass the name of the database and re-bind your control

Note: you have to store your queries as stored procedures in each database, or you have to store a very long dictionary, and that makes no sense.

OK, i did it for .mdf database and i'm not familiar with db, and you're using .sdf db. I don't know if there will be a problem ??!

[mldisibio]

Actually, you can modify your app.config file at runtime. You can also store multiple connection strings in the connectionStrin g section, or you can dynamically add new ones as the application is running.

To see an example of opening, modifying and saving the app.config file, see: ConfigurationMa nager.RefreshSe ction Method (System.Configu ration)

For an example of adding a new connectionStrin g to the configuration file, see:
ConnectionStrin gSettingsCollec tion.Add Method (System.Configu ration)