C# Stored Procedure Return Scalar

Question

I have a stored procedure that will return either a 1 or 0. I cannot seem to properly wrap it in a C# function. Any help is appreciated.

Here is my stored procedure (that I've tested in SQL Server and it works):

CREATE PROCEDURE VerifyAccount
    @Email VARCHAR(50),
    @Pass VARCHAR(100)
AS
BEGIN
    SET NOCOUNT ON;

    DECLARE @Salt CHAR(25);
    DECLARE @PwdWithSalt VARCHAR(125);
    DECLARE @PwdHash VARBINARY(20);  

    SELECT @Salt = Salt, @PwdHash = Pass 
    FROM users 
    WHERE EMAIL = @Email;

    SET @PwdWithSalt = @Salt + @Pass;

    IF (HASHBYTES('SHA1', @PwdWithSalt) = @PwdHash)
        RETURN 1;
    ELSE
        RETURN 0;
END;

If I open up a new SQL query and run this code, it works:

DECLARE @Result INT;

EXEC @Result = VerifyAccount 
                   @Email = 'myemail@email.com', @Pass = 'Str0ngP@ssw0rd!';
SELECT @Result;

When I try to wrap it in C# code, It returns a -1 value, which is not possible with this procedure. It should return a "1". What am I doing wrong?

public static int ValidateUser(User user)
{
    int result = 0;
    
    using (SqlConnection conn = new SqlConnection(SQLQuery.connDb))
    {
        using (var command = new SqlCommand("VerifyAccount", conn)
        {
            CommandType = CommandType.StoredProcedure,
            Parameters =
            {
                new SqlParameter("@Email", user.Email),
                new SqlParameter("@Pass", user.Password)
            }
        })
        {
            try
            {
                conn.Open();
                result = command.ExecuteNonQuery();
                conn.Close();
            }
            catch (Exception e)
            {
                result = -15;
                Console.WriteLine(e.Message);
            }
            finally
            {
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                }
            }
        }
    }

    return result;
 }

Answer 1

ExecuteNonQuery returns the number of rows affected

You need

  result =  (int)command.ExecuteScalar();

Answer 2

Here is how you read the return value fro Stored Procedures.

public static int ValidateUser(User user)
{
    int result = 0;
    
    using (SqlConnection conn = new SqlConnection(SQLQuery.connDb))
    {
        using (var command = new SqlCommand("VerifyAccount", conn)
        {
            CommandType = CommandType.StoredProcedure,
            Parameters =
            {
                new SqlParameter("@Email", user.Email),
                new SqlParameter("@Pass", user.Password)
            }
        })
        {
            try
            {
            
                // STEP 01: **** SETUP UP RETURN VALUE STORED PROCEDURES *****
                var returnParameter = command.Parameters.Add("@ReturnVal", SqlDbType.Int);
                returnParameter.Direction = ParameterDirection.ReturnValue;
                
                conn.Open();
                result = command.ExecuteNonQuery();
                
                // STEP 02: **** READ RETURN VALUE *****
                var result = returnParameter.Value;
                
                conn.Close();
            }
            catch (Exception e)
            {
                result = -15;
                Console.WriteLine(e.Message);
            }
            finally
            {
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                }
            }
        }
    }
    return result;
 }