Question

Is it possible to change a database connection string value in the Web.Config at runtime without reloading the application domain? The reason for doing this is that:

1. I am building a multi-tenanted application which uses the one code instance and multiple databases instances approach, so the database connection string in the web.config must be able to be changed at runtime for different tenant users.

2. ADO.NET always injecst the database connection string in the web.config when you are using entity framework/LINQ to SQL etc, dataset etc.

So I may have to do something weird like this. Hope it is clear enough. Thanks a lot!

Answer 1

Yes it is possible.
try this

System.Configuration.Configuration conf = WebConfigurationManager.OpenWebConfiguration(Server.MapPath);
conf.ConnectionStrings.ConnectionStrings["comp1"].ConnectionString = _connection_comp1;
conf.ConnectionStrings.ConnectionStrings["comp2"].ConnectionString = _connection_comp2;
conf.AppSettings.Settings["CompanyCode"].Value = _company_code;
conf.Save();