Returns with parameters in SQL Server

Server CREATE PROCEDURE Loginuser
@loginUN Char OUTPUT,
@loginPW Char (40)
As
If @loginPW = (select [Password] from users where Username= @loginUN)
return 0;
Else
return-1;

Go

To Loginun the return value, define it as output, and the corresponding SqlCommand parameter definition also defines the parameterdirect.inputoutput type, so that when the value of the Loginun is changed in the stored procedure, it is returned.
You can determine the return value of SqlCommand.ExecuteNonQuery (), 0 for success, and less than 0 for failure.