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I have defined a class "Seller" in this I am using a public string variable as
public string _connectionString = ConfigurationManager.ConnectionStrings["seller"].ConnectionString.ToString();
The above connection string is defined in App.config file used in class library Seller.
When I am calling class Seller
Seller _seller = new Seller();
It throws error " Object reference not set to an instance of an object" when the cursor reads the above string object??
Its very irritating Error. I tried every thing but didn,t found any solution. Please help on this.