c#連結資料庫

 //資料庫
    public class GF_DA
    {
/// <summary>
/// 執行SQL語句 sConnStr 連接字串,sql執行的sql命令 返回第一行第一列
/// </summary>
/// <param name="sConnStr"></param>
/// <param name="sql"></param>
/// <returns></returns>
        public static object ExecSQL(string sConnStr, string sql)
        {
using (SqlConnection conn = new SqlConnection(sConnStr))
            {
using (SqlCommand cmd = new SqlCommand())
                {
try
                    {
                        conn.Open();
                        cmd.Connection = conn;
                        cmd.CommandText = sql;
return cmd.ExecuteScalar();
                    }
catch
                    {
return null;
                    }
                }

            }
        }

/// <summary>
/// 執行SQL數組  
/// </summary>
/// <param name="sConnStr"></param>
/// <param name="alSql"></param>
/// <param name="iLen"></param>
        public static void ExecSQL(string sConnStr, ArrayList alSql, int iLen)
        {
using (SqlConnection conn = new SqlConnection(sConnStr))
            {
using (SqlCommand cmd = new SqlCommand())
                {
try
                    {
                        conn.Open();
                        cmd.Connection = conn;
for (int i = 0; i < alSql.Count; i++)
                        {
                            cmd.CommandText = alSql[i].ToString();
                            cmd.ExecuteNonQuery();

                        }
                    }
catch
                    {

                    }
                }

            }
        }

/// <summary>
/// 填充資料 返回DataTable
/// </summary>
/// <param name="sConnStr"></param>
/// <param name="sql"></param>
/// <param name="sTableName"></param>
/// <returns></returns>
        public static DataTable DataFill(string sConnStr, string sql, string sTableName)
        {
using (SqlConnection conn = new SqlConnection(sConnStr))
            {
using (SqlCommand cmd = new SqlCommand())
                {
                    DataSet ds = new DataSet();
try
                    {
                        conn.Open();
                        cmd.Connection = conn;
                        cmd.CommandText = sql;
                        SqlDataAdapter ap = new SqlDataAdapter(cmd);
                        ap.Fill(ds, sTableName);
return ds.Tables[0];
                    }
catch
                    {
return null;
                    }
                }


            }
        }
    }