.net core

需要引入包：

Dapper
Dapper.Contrib

　　

接口代码：

/// <summary>
/// Dapper上下文
/// </summary>
public interface IDapperContext : IDisposable
{
    /// <summary>
    /// 数据库连接对象
    /// </summary>
    IDbConnection Connection { get; }
}

/// <summary>
/// 数据库CRUD等操作
/// </summary>
/// <typeparam name="T"></typeparam>
public interface IRepository<T> where T : class
{
    /// <summary>
    /// 连接
    /// </summary>
    IDbConnection Connection { get; }

    /// <summary>
    /// 上下文
    /// </summary>
    IDapperContext Context { get; }

    /// <summary>
    /// 设置上下文连接字符串
    /// </summary>
    /// <param name="connectionString">字符串</param>
    void SetContext(string connectionString);

    /// <summary>
    /// 重置上下文，用appSetting.json里的数据库连接串
    /// </summary>
    void ResetContext();

    /// <summary>
    /// 获取分页数据
    /// </summary>
    /// <typeparam name="TEntity"></typeparam>
    /// <param name="criteria">查询设置</param>
    /// <param name="param"></param>
    /// <returns></returns>
    PageDataView<TEntity> GetPageData<TEntity>(PageCriteria criteria, object param = null) where TEntity : class;


    /// <summary>
    /// 根据主键获取数据
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="key"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    T GetByKey<T>(object key, IDbTransaction transaction = null, int? commandTimeout = null) where T : class;

    /// <summary>
    /// 添加数据
    /// </summary>
    /// <param name="entity"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    long Add(T entity, IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="entity"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    void Update(T entity, IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 删除单条数据
    /// </summary>
    /// <param name="entity"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    void Remove(T entity, IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 根据主键获取数据
    /// </summary>
    /// <param name="key"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    T GetByKey(object key, IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 获取所有数据
    /// </summary>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    IEnumerable<T> GetAll(IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 根据条件获取数据列表
    /// </summary>
    /// <param name="where"></param>
    /// <param name="order"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    IEnumerable<T> GetBy(object where = null, object order = null, IDbTransaction transaction = null, int? commandTimeout = null);

    IEnumerable<T> GetBy<T>(object sql = null, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class;

    T QuerySingleOrDefault<T>(string sql = null, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class;

    /// <summary>
    /// 查询数据列表
    /// </summary>
    /// <param name="sql"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    IEnumerable<dynamic> Query(string sql, IDbTransaction transaction = null, int? commandTimeout = null);


    /// <summary>
    /// 查询数据列表
    /// </summary>
    /// <param name="sql"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    IEnumerable<T> Query<T>(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class;


    /// <summary>
    /// 查询数据列表
    /// </summary>
    /// <typeparam name="TFirst"></typeparam>
    /// <typeparam name="TSecond"></typeparam>
    /// <typeparam name="TReturn"></typeparam>
    /// <param name="sql"></param>
    /// <param name="map"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    IEnumerable<TReturn> Query<TFirst, TSecond, TReturn>(string sql, Func<TFirst, TSecond, TReturn> map, object param = null, IDbTransaction transaction = null, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);


    IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TReturn>(string sql, Func<TFirst, TSecond, TThird, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);

    IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);

    IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);

    IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TSeventh, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TSeventh, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);
    /// <summary>
    /// 查询数据列表
    /// </summary>
    /// <typeparam name="TFirst"></typeparam>
    /// <typeparam name="TSecond"></typeparam>
    /// <typeparam name="TThird"></typeparam>
    /// <typeparam name="TFourth"></typeparam>
    /// <typeparam name="TReturn"></typeparam>
    /// <param name="sql"></param>
    /// <param name="map"></param>
    /// <param name="param"></param>
    /// <param name="transaction"></param>
    /// <param name="splitOn"></param>
    /// <param name="commandTimeout"></param>
    /// <param name="commandType"></param>
    /// <returns></returns>
    IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TReturn> map, object param = null, IDbTransaction transaction = null, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null);

    /// <summary>
    /// 执行sql
    /// </summary>
    /// <param name="sql"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    int Excute(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null);

    /// <summary>
    /// 返回单个参数
    /// </summary>
    /// <param name="sql"></param>
    /// <param name="transaction"></param>
    /// <param name="commandTimeout"></param>
    /// <returns></returns>
    object ExcuteScalar(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null);

    GridReader QueryMultiple(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null);
}

　　

实现：

public class DapperContext : IDapperContext
{
    /// <summary>
    /// 连接字符串
    /// </summary>
    private string _connectionString;

    private bool _useMiniProfiling;

    /// <summary>
    /// 连接
    /// </summary>
    private IDbConnection _connection;

    ///// <summary>
    ///// 节点对象
    ///// </summary>
    //private readonly AppSetting _appSetting;

    /// <summary>
    /// 构造函数注入IOptions
    /// </summary>
    /// <param name="appSetting"></param>
    public DapperContext(IConfiguration configuration)
    {
        _connectionString = configuration["AppSetting:ConnectionString"];
        _useMiniProfiling = bool.Parse(configuration["AppSetting.UseMiniProfiling"]);
    }

    /// <summary>
    /// 连接字符串，用于各个公司
    /// </summary>
    /// <param name="connectionString"></param>
    public DapperContext(string connectionString)
    {
        _connectionString = connectionString;
    }

    /// <summary>
    /// 获取连接
    /// </summary>
    public IDbConnection Connection
    {
        get
        {
            if (_connection == null || _connection.State == ConnectionState.Closed)
            {
                if (_useMiniProfiling)
                {
                    _connection = new ProfiledDbConnection(new SqlConnection(_connectionString), MiniProfiler.Current);
                }
                else
                {
                    _connection = new SqlConnection(_connectionString);
                }
            }
            if (_connection.State != ConnectionState.Open)
            {
                //Console.WriteLine("数据库连接：" + _connectionString);
                _connection.Open();
            }
            return _connection;
        }
    }

    /// <summary>
    /// 释放连接
    /// </summary>
    public void Dispose()
    {
        if (_connection != null && _connection.State == ConnectionState.Open)
            _connection.Close();
    }
}

　　

    public class Repository<T> : IRepository<T> where T : class
    {
        public IDbConnection Connection
        {
            get
            {
                return Context.Connection;
            }
        }

        /// <summary>
        /// 存储appsetting.json里的数据库连接字符串
        /// </summary>
        private string _connectionString;

        public IDapperContext Context { get; private set; }

        public Repository(IDapperContext context)
        {
            Context = context;
            _connectionString = context.Connection.ConnectionString;
        }

        /// <summary>
        /// 设置上下文连接字符串
        /// </summary>
        /// <param name="connectionString"></param>
        public void SetContext(string connectionString)
        {
            Context.Dispose();
            Context = new DapperContext(connectionString);
        }
        
        /// <summary>
        /// 重置上下文，用appSetting.json里的数据库连接串
        /// </summary>
        public void ResetContext()
        {
            SetContext(_connectionString);
        }

        public PageDataView<TEntity> GetPageData<TEntity>(PageCriteria criteria, object param = null) where TEntity : class
        {
            var p = new DynamicParameters();
            string proName = "CCHRWebApiProcGetPageData";
            p.Add("TableName", criteria.TableName);
            p.Add("PrimaryKey", criteria.PrimaryKey);
            p.Add("Fields", criteria.Fields);
            p.Add("Condition", criteria.Condition);
            p.Add("CurrentPage", criteria.CurrentPage);
            p.Add("PageSize", criteria.PageSize);
            p.Add("Sort", criteria.Sort);
            p.Add("RecordCount", dbType: DbType.Int32, direction: ParameterDirection.Output);
            var pageData = new PageDataView<TEntity>();
            int excuteTimes = 0;
            //QUERY:
            try
            {
                pageData.Items = Connection.Query<TEntity>(proName, p, commandType: CommandType.StoredProcedure, commandTimeout:300).ToList();
                pageData.TotalNum = p.Get<int>("RecordCount");
                pageData.TotalPageCount = Convert.ToInt32(Math.Ceiling(pageData.TotalNum * 1.0 / criteria.PageSize));
                pageData.CurrentPage = criteria.CurrentPage > pageData.TotalPageCount ? pageData.TotalPageCount : criteria.CurrentPage;
            }
            catch (Exception e)
            {
                excuteTimes++;
                if (e.Message.Contains("找不到存储过程 'CCHRWebApiProcGetPageData'") && excuteTimes <= 3)
                {
                    FileStream fileStream = new FileStream(@"SqlCCHRWebApiProcGetPageData.sql", FileMode.Open);
                    StreamReader sr = new StreamReader(fileStream);
                    string sql = sr.ReadToEnd();
                    if (fileStream != null)
                        fileStream.Close();
                    if (sr != null)
                        sr.Close();
                    if (!string.IsNullOrEmpty(sql))
                    {
                        Connection.Execute(sql);
                       // goto QUERY;
                    }
                    throw;
                }
                else if ((e.Message.Contains("远程主机强迫关闭了一个现有的连接") || e.Message.Contains("指定的网络名不再可用")) && excuteTimes <= 3)
                {
                    System.Threading.Thread.Sleep(excuteTimes * 1000);
                    //goto QUERY;
                }
                else
                {
                    throw;
                }
            }
            return pageData;
        }

        public virtual T GetByKey<T>(object id, IDbTransaction transaction = null, int? commandTimeout = null) where T : class
        {
            if (id == null)
            {
                throw new ArgumentNullException("id");
            }
            return Connection.Get<T>(id, transaction: transaction, commandTimeout: commandTimeout);
        }

        public long Add(T entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (entity == null)
            {
                throw new ArgumentNullException("entity", "Add to DB null entity");
            }
            var res = Connection.Insert(entity, transaction: transaction, commandTimeout: commandTimeout);
            return res;
        }

        public virtual void Update(T entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (entity == null)
            {
                throw new ArgumentNullException("entity", "Update in DB null entity");
            }
            Connection.Update(entity, transaction: transaction, commandTimeout: commandTimeout);
        }

        public virtual void Remove(T entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (entity == null)
            {
                throw new ArgumentNullException("entity", "Remove in DB null entity");
            }
            Connection.Delete(entity, transaction: transaction, commandTimeout: commandTimeout);
        }

        public virtual T GetByKey(object id, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (id == null)
            {
                throw new ArgumentNullException("id");
            }
            return Connection.Get<T>(id, transaction: transaction, commandTimeout: commandTimeout);
        }

        public virtual IEnumerable<T> GetAll(IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return Connection.GetAll<T>(transaction: transaction, commandTimeout: commandTimeout);
        }


        public virtual T QuerySingleOrDefault<T>(string sql = null, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class
        {
            return Connection.QuerySingleOrDefault<T>(sql, param, transaction: transaction, commandTimeout: commandTimeout);
        }

        public virtual IEnumerable<T> GetBy(object where = null, object order = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return Connection.Query<T>(where.ToString(), commandTimeout:commandTimeout);
        }

        public virtual IEnumerable<T> GetBy<T>(object sql = null, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class
        {
            return Connection.Query<T>(sql.ToString(), param: param, transaction: transaction, commandTimeout: commandTimeout);
        }


        public IEnumerable<dynamic> Query(string sql, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return Connection.Query<dynamic>(sql);
        }

        public IEnumerable<T> Query<T>(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) where T : class
        {
            return Connection.Query<T>(sql, param: param, transaction: transaction);
        }

        public IEnumerable<TReturn> Query<TFirst, TSecond, TReturn>(string sql, Func<TFirst, TSecond, TReturn> map, object param = null, IDbTransaction transaction = null, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);
        }
        public IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TReturn>(string sql, Func<TFirst, TSecond, TThird, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TThird, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);
        }

        public IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TReturn> map, object param = null, IDbTransaction transaction = null, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TThird, TFourth, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);
        }

        public IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TThird, TFourth, TFifth, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);

        }
        public IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);
        }
        public IEnumerable<TReturn> Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TSeventh, TReturn>(string sql, Func<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TSeventh, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, CommandType? commandType = null)
        {
            return Connection.Query<TFirst, TSecond, TThird, TFourth, TFifth, TSixth, TSeventh, TReturn>(sql, map, param: param, transaction: transaction, splitOn: splitOn, commandType: commandType);
        }

        public int Excute(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return Connection.Execute(sql, param: param, transaction: transaction);
        }
        public object ExcuteScalar(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return Connection.ExecuteScalar(sql, param: param, transaction: transaction, commandTimeout: commandTimeout);
        }

        public GridReader QueryMultiple(string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null) {

            return Connection.QueryMultiple(sql, param: param, transaction: transaction, commandTimeout: commandTimeout);
        } 
    }