Get Connection With Specific SQL Database for different user

HI,

 

Maintain All connection string in web.config

 

Those userID based fetch connectionstring from web.config

or else

keep connection string in user table

 

example 

 private string _connectionString => ConfigurationManager.AppSettings[Companyname].ToString()

hi, you have to create one master database in which you maintain the entity like a company so that using that company ID you can fetch the data for respective entity or company.

 

So you can access the data by using the specific company user credential only.