c# - How to set connectionstring for DbExtensions/SqlBuilder? -

i using dbextensions/sqlbuilder.md project. , during connection getting following error.

a default provider name must provided using 'dbextensions:defaultprovidername' key in appsettings configuration section.

my connectionstring in session object. here code.

database db = new database(helperclass.connectionstring); 

finally got solution. add key in web.config file.

 <add key="dbextensions:defaultprovidername" value ="system.data.sqlclient"/> 

and work.