sql trigger & c#

Question

hi everyone.please help me...

why the message of RAISERROR in sql trigger, does'nt display in c# at runtime when my c# codes are running?????

 plssssssssssssssssss

***************my sql trigger 

CREATE TRIGGER [dbo].[trg_CheckBalance_me]

ON [dbo].[st_havaleh_info]

FOR INSERT,update

AS

BEGIN

SET NOCOUNT ON;

if ((select count_kala from st_seating where Code_kala=(select code_material from inserted )) < ((select count_unit from inserted)-(select count_unit from deleted)))

begin

ROLLBACK TRAN;

RAISERROR ('stock of materials are low in store', 16, 1);

return

end

END;

go

 

 

 **********************************c# code

try

{

if ((checkdate == true) && con.Back_Query("select output_no from st_havaleh_info where output_no='" + txt_output.Text + "' and code_material='" + txt_code_k.Text + "'") != "0")

if (MessageBox.Show("?????? ?????", "??????", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1, MessageBoxOptions.RightAlign) == DialogResult.Yes)

{

string query5 = "update st_havaleh_info set count_unit='" + txt_count.Text + "',code_material='" + txt_code_k.Text + "',name_material=N'" + txt_name_k.Text + "',opposite_party='" + txt_name_opposite.Text + "'"

+ ",code_unit='" + unit_code_1 + "' ,description=N'" + txt_des.Text + "' where output_no='" + txt_output.Text + "' and code_material='" + txt_code_k.Text + "'";

con.ExecuteNonQuery(query5, 1);

}

}

catch (Exception ex)

{

if (ex.InnerException != null)

{

Console.WriteLine(ex.InnerException.Message);

}

}

*************************************************call connectionclass.executeNonQuery

 

public string ExecuteNonQuery(string CommandText,int par)

{

try

{

connection.Close();

connection.ConnectionString = ConnectionString;

connection.Open();

command.CommandText = CommandText;

command.Connection = connection;

command.ExecuteNonQuery();

command.Dispose();

connection.Close();

if(par==1)

MessageBox.Show("done");

return "1";

}

catch

{

if (par == 1)

MessageBox.Show("error in saving");

return "0";

}

}

***************************************************************