error message to be displayed if columns in the uploaded excel are not matching

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C#3.0

C#

ASP.NET

DataTable dtAttributes = objDAL.GetCPRAttributes();
        foreach (DataRow row in dTableSql.Rows)
        {
            DataRow[] rows = dtAttributes.Select("Attributes='" + row["Attributes"] + "'");

            if (rows != null && rows.Length > 0)
                count++;
        }
        if (count < 13)
        {
            throw new Exception("Invalid Excel");
          
           
        }

here i used throw new exception...this is my code in BAL ....i want this exception in the front end ....

in the cs page

catch (Exception ex)
       {

           Console.WriteLine(ex);
       }

i had something like this
here its catching my exception

But i want to be displayed as a message ..