inserción masiva en sql

Entonces puedes hacerlo del modo que te expuse en el link, creas un tipo de dato tabla

CREATE TYPE [dbo].[testParam] AS TABLE(
    [id] [int] NOT NULL,
    [val1] [varchar](50) NULL,
    [val2] [varchar](50) NULL,
    PRIMARY KEY CLUSTERED
(
    [id] ASC
)WITH (IGNORE_DUP_KEY = OFF)
)
GO

CREATE TABLE [dbo].[testing](
    [id] [int] NOT NULL,
    [val1] [varchar](50) NOT NULL,
    [var2] [varchar](50) NOT NULL,
 CONSTRAINT [PK_testing] PRIMARY KEY CLUSTERED
(
    [id] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

Creas el procedure que recibe el lote en una tabla

create procedure test @param testParam readonly
as
insert into dbo.testing
select * from @param;

Y lo invocas asi desde el SSMS

declare @par testParam
insert into @par  VALUES (1, 'Manuela','Vera')
insert into @par  VALUES (2, 'Josefa','Medina')
insert into @par  VALUES (3, 'Pablo','Garmendia')
execute dbo.test @param = @par
select * from dbo.testing

y si necesitas de una aplicacion en .net

try
{
    var dataTable = new DataTable();
    dataTable.Columns.Add("Id", typeof(int));
    dataTable.Columns.Add("val1", typeof(string));
    dataTable.Columns.Add("val2", typeof(string));
    dataTable.Rows.Add(1, "Jose", "Rodriguez");
    dataTable.Rows.Add(2, "María", "Benitez");
    dataTable.Rows.Add(3, "Marcela", "Troche");
    using (var conn = new SqlConnection("Server=10.10.10.1;Initial Catalog=devtroce;user ID=devtroce;password=*********"))
    {
        using (var cmd = new SqlCommand("test", conn))
        {
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddWithValue("@param", dataTable);
            conn.Open();
            cmd.ExecuteNonQuery();
            MessageBox.Show("guardado con éxito");
        }
    }
}
catch(Exception ex)
{
    MessageBox.Show(ex.Message);
}