常用的查询的方法

返回一个Table的方法！

   public static DataTable GetDataTable(string sql)
        {
            DataTable dt = new DataTable();
            if (!string.IsNullOrEmpty(sql))
            {
                SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbString"].ConnectionString);

                try
                {
                    conn.Open();
                    SqlDataAdapter da = new SqlDataAdapter(sql, conn);
                    da.Fill(dt);
                }
                catch (Exception ex)
                {
                    throw ex;
                }
                finally
                {
                    conn.Close();
                }


            }

            return dt;
        }

返回受影响的行数！

public static int ExecuteNonQuery(string sql, SqlParameter[] sqlParams)
        {
            int count = 0;

            SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbString"].ConnectionString);

            if (!string.IsNullOrEmpty(sql) && sqlParams != null && sqlParams.Length > 0)
            {
                try
                {
                    conn.Open();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    cmd.Parameters.AddRange(sqlParams);
                    count = cmd.ExecuteNonQuery();

                }
                catch (Exception ex)
                {
                    throw ex;
                }
                finally
                {
                    conn.Close();
                }

            }

            return count;
        }