[C#] 改进SqliteHelper, 减少拼接SQL语句

说明：开始几个是基本的方法，后面稍微封装了下

 public class SqliteHelper
     {
         //连接字符串
         private static readonly string str = ConfigurationManager.ConnectionStrings["conStr"].ConnectionString;

         /// <summary>
         /// 增删改
         /// 20180723
         /// </summary>
         /// <param name="sql">sql语句</param>
         /// <param name="param">sql参数</param>
         /// <returns>受影响的行数</returns>
         public static int ExecuteNonQuery(string sql, params SQLiteParameter[] param)
         {
             //try
             //{
                 using (SQLiteConnection con = new SQLiteConnection(str))
                 {
                     using (SQLiteCommand cmd = new SQLiteCommand(sql, con))
                     {
                         con.Open();
                         if (param != null)
                         {
                             cmd.Parameters.AddRange(param);
                         }

                         string sql2 = cmd.CommandText;
                         //con.Close();
                         return cmd.ExecuteNonQuery();
                     }
                 }
             //}
             //catch (SQLiteException se)
             //{
             //    return 0;
             //}
         }

         /// <summary>
         /// 查询
         /// 20180723
         /// </summary>
         /// <param name="sql">sql语句</param>
         /// <param name="param">sql参数</param>
         /// <returns>首行首列</returns>
         public static object ExecuteScalar(string sql, params SQLiteParameter[] param)
         {
             using(SQLiteConnection con = new SQLiteConnection(str))
             {
                 using(SQLiteCommand cmd = new SQLiteCommand(sql, con))
                 {
                     con.Open();
                     if (param != null)
                     {
                         cmd.Parameters.AddRange(param);
                     }

                     return cmd.ExecuteScalar();
                 }
             }
         }

         /// <summary>
         /// 多行查询
         /// 20180723
         /// </summary>
         /// <param name="sql">sql语句</param>
         /// <param name="param">sql参数</param>
         /// <returns>SQLiteDateReader</returns>
         public static SQLiteDataReader ExecuteReader(string sql, params SQLiteParameter[] param)
         {
             using (SQLiteConnection con = new SQLiteConnection(str))
             {
                 using (SQLiteCommand cmd = new SQLiteCommand(sql, con))
                 {
                     if (param != null)
                     {
                         cmd.Parameters.AddRange(param);
                     }
                     try
                     {
                         con.Open();
                         return cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
                     }
                     catch (Exception ex)
                     {
                         con.Close();
                         con.Dispose();
                         throw ex;
                     }
                 }
             }

         }

         /// <summary>
         /// 查询多行数据
         /// 20180723
         /// </summary>
         /// <param name="sql">sql语句</param>
         /// <param name="param">sql参数</param>
         /// <returns>一个表</returns>
         public static DataTable ExecuteTable(string sql, params SQLiteParameter[] param)
         {
             DataTable dt = new DataTable();
             using (SQLiteDataAdapter sda = new SQLiteDataAdapter(sql, str))
             {
                 if (param != null)
                 {
                     sda.SelectCommand.Parameters.AddRange(param);
                 }
                 sda.Fill(dt);
             }
             return dt;
         }

         /// <summary>
         /// 查询封装
         /// 20180725
         /// </summary>
         /// <param name="tbName">表名</param>
         /// <param name="fields">查询需要的字段名："id, name, age"</param>
         /// <param name="where">查询条件："id = 1"</param>
         /// <param name="orderBy">排序："id desc"</param>
         /// <param name="limit">分页："0,10"</param>
         /// <param name="param">sql参数</param>
         /// <returns>受影响行数</returns>
         public static DataTable QueryTable(string tbName, string fields = "*", string where = "", string orderBy = "", string limit = "", params SQLiteParameter[] param)
         {
             //排序
             if (orderBy != "")
             {
                 orderBy = "ORDER BY " + orderBy;//Deom: ORDER BY id desc
             }

             //分页
             if (limit != "")
             {
                 limit = "LIMIT " + limit;//Deom: LIMIT 0,10
             }

             string sql = string.Format("SELECT {0} FROM `{1}` WHERE {2} {3} {4}", fields, tbName, where, orderBy, limit);

             //return sql;
             return SqliteHelper.ExecuteTable(sql, param);

         }

         /// <summary>
         /// 数据插入
         /// 20180725
         /// </summary>
         /// <param name="tbName">表名</param>
         /// <param name="insertData">需要插入的数据字典</param>
         /// <returns>受影响行数</returns>
         public static int ExecuteInsert(string tbName, Dictionary<String , String> insertData)
         {
             string point = "";//分隔符号(,)
             string keyStr = "";//字段名拼接字符串
             string valueStr = "";//值的拼接字符串

             List<SQLiteParameter> param = new List<SQLiteParameter>();
             foreach (string key in insertData.Keys)
             {
                 keyStr += string.Format("{0} `{1}`", point, key);
                 valueStr += string.Format("{0} @{1}", point, key);
                 param.Add(new SQLiteParameter("@"+key, insertData[key]));
                 point = ",";
             }
             string sql = string.Format("INSERT INTO `{0}`({1}) VALUES({2})", tbName, keyStr, valueStr);

             //return sql;
             return ExecuteNonQuery(sql, param.ToArray());

         }

         /// <summary>
         /// 执行Update语句
         /// 20180725
         /// </summary>
         /// <param name="tbName">表名</param>
         /// <param name="where">更新条件：id=1</param>
         /// <param name="insertData">需要更新的数据</param>
         /// <returns>受影响行数</returns>
         public static int ExecuteUpdate(string tbName, string where, Dictionary<String, String> insertData)
         {
             string point = "";//分隔符号(,)
             string kvStr = "";//键值对拼接字符串(Id=@Id)

             List<SQLiteParameter> param = new List<SQLiteParameter>();
             foreach (string key in insertData.Keys)
             {
                 kvStr += string.Format("{0} {1}=@{2}",point, key, key);
                 param.Add(new SQLiteParameter("@" + key, insertData[key]));
                 point = ",";
             }
             string sql = string.Format("UPDATE `{0}` SET {1} WHERE {2}", tbName, kvStr, where);

             return ExecuteNonQuery(sql, param.ToArray());

         }

     }