c# - How to check if connection string is valid?

Question

I'm writing an application where a user provides a connection string manually and I'm wondering if there is any way that I could validate the connection string - I mean check if it's correct and if the database exists.

Answer 1

You could try to connect? For quick (offline) validation, perhaps use DbConnectionStringBuilder to parse it...

    DbConnectionStringBuilder csb = new DbConnectionStringBuilder();
    csb.ConnectionString = "rubb ish"; // throws

But to check whether the db exists, you'll need to try to connect. Simplest if you know the provider, of course:

    using(SqlConnection conn = new SqlConnection(cs)) {
        conn.Open(); // throws if invalid
    }

If you only know the provider as a string (at runtime), then use DbProviderFactories:

    string provider = "System.Data.SqlClient"; // for example
    DbProviderFactory factory = DbProviderFactories.GetFactory(provider);
    using(DbConnection conn = factory.CreateConnection()) {
        conn.ConnectionString = cs;
        conn.Open();
    }