Select multiple values from listbox and insert in SQL db

Question

Hi!
I'm working on an ASP.NET website in C#. The idea is to insert data into a SQL Server database through the website. I wrote a stored procedure for insert data and code in C#. The data from Table 3 is inserting through Listbox, but as a string, not as foreign key. I think that is a bad way because of searching data.
Does anyone have an idea hot to insert ID from Table 3 in Table 1, through Listbox, if I select multiple text values from that table?
Fields in Table 3: ID, col5.

This is stored procedure.

 

SET ANSI_NULLS ON

GO

SET QUOTED_IDENTIFIER ON

GO

ALTER PROCEDURE [dbo].[TEST]

// Table1

@col1 NVARCHAR(MAX),

@col2 NVARCHAR(MAX),

@col3 NVARCHAR(MAX),

@col4 NVARCHAR(MAX),

// Table 2

@FileName NVARCHAR(50),

@FilePath NVARCHAR(200),

// Table 3

 @col4 NVARCHAR(MAX)

 

AS

BEGIN

SET NOCOUNT ON;

DECLARE @Table_Var TABLE (ID1 INT)

INSERT INTO Table1 (col1,col2,col3,col4,COL5)

OUTPUT inserted.ID1

INTO @Table_Var(ID1)

SELECT @col1,@col2,@col3,@col4, @COL5

INSERT INTO Table2 (colID,FileName,FilePath)

SELECT ID1,@FileName,@FilePath

FROM @Table_Var

END

 

This is part of code that is inserting text value from Table 3, through Listbox and Label.

 

foreach (ListItem item in Table3.Items)

{

if (item.Selected)

{

try

{

Label1.Text = item.Text + ", " + Label1.Text;

cmd.Parameters["@COL5"].Value = Label1.Text;

}

catch (Exception ex)

{

}

}

}