经销商项目一

• 核心层

1. DealerPlatform.Core

SqlHelper类

public class SqlHelper
    {
        public static string ConStr { get; set; }

        /// <summary>
        /// 查询数据获取表格
        /// </summary>
        /// <param name="sqlText"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static DataTable ExecuteDataTable(string sqlText,SqlParameter[] parameters)
        {
            //修一条路去目的
            using SqlConnection conn = new SqlConnection(ConStr);
            //打开路的关卡
            conn.Open();
            //操作员通过conn这条路，去目的地取sqlText中指定的东西
            SqlCommand cmd = new SqlCommand(sqlText,conn);
            //对指令的补充
            cmd.Parameters.AddRange(parameters);
            //操作员根据cmd中的命令，去仓库找东西（适配命令）
            SqlDataAdapter adapter = new SqlDataAdapter(cmd);
            //车子的车厢
            DataSet ds = new DataSet();
            //小推车把取到的东西装入车厢
            adapter.Fill(ds);
            return ds.Tables[0];

        }

        /// <summary>
        /// 返回增删改后受影响的行数
        /// </summary>
        /// <param name="sqlText"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static int ExecuteNonQuery(string sqlText, SqlParameter[] parameters)
        {
            //修一条路去目的
            using SqlConnection conn = new SqlConnection(ConStr);
            //打开路的关卡
            conn.Open();
            //操作员通过conn这条路，去目的地取sqlText中指定的东西
            SqlCommand cmd = new SqlCommand(sqlText, conn);
            //对指令的补充
            cmd.Parameters.AddRange(parameters);
            int rows= cmd.ExecuteNonQuery();
            return rows;
        }

        /// <summary>
        /// 返回第一行第一列
        /// </summary>
        /// <param name="sqlText"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sqlText, SqlParameter[] parameters)
        {
            //修一条路去目的
            using SqlConnection conn = new SqlConnection(ConStr);
            //打开路的关卡
            conn.Open();
            //操作员通过conn这条路，去目的地取sqlText中指定的东西
            SqlCommand cmd = new SqlCommand(sqlText, conn);
            //对指令的补充
            cmd.Parameters.AddRange(parameters);
            object obj = cmd.ExecuteScalar();
            return obj;
        }

        /// <summary>
        /// c#的null转成db的dbnull
        /// </summary>
        /// <param name="p"></param>
        /// <returns></returns>
        public static object ToDBNull(object p)
        {
            return p == null ? DBNull.Value : null;
        }

        /// <summary>
        /// db的dbnull转成c#的null
        /// </summary>
        /// <param name="p"></param>
        /// <returns></returns>
        public static object ToNull(object p)
        {
            return p == DBNull.Value ? null : p;
        }
    }

• DealerPlatform.Api

• startup

public void ConfigureServices(IServiceCollection services)
        {
            //配置连接字符串
            SqlHelper.ConStr = Configuration.GetConnectionString("ConStr");
            services.AddControllers();
            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "DealerPlatform.Api", Version = "v1" });
            });
        }