dapper

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工具类

需要安装nuget包：dapper、dapper.contrib

public class DapperHelper
    {

        //数据库连接字符串
        private string connectionString;

        public DapperHelper(string connectionString)
        {
            this.connectionString = connectionString;
        }


        //private  readonly string connectionString = "Server=127.0.0.1;Database=shuigong;Uid=root;Pwd=123456;";

        public DbConnection GetDbConnection()
        {
            DbConnection connection =new OracleConnection(connectionString);
            connection.Open();
            return connection;
        }


        /// <summary>
        /// 查询列表
        /// </summary>
        /// <param name="sql">查询的sql</param>
        /// <param name="param">替换参数</param>
        /// <returns></returns>
        public List<T> Query<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.Query<T>(sql, param).ToList();
            }
        }

        /// <summary>
        /// 查询列表
        /// </summary>
        /// <param name="sql">查询的sql</param>
        /// <param name="param">替换参数</param>
        /// <returns></returns>
        public IEnumerable<dynamic> Query(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.Query(sql, param);
            }
        }

        /// <summary>
        /// 查询第一个数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public T QueryFirst<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QueryFirst<T>(sql, param);
            }
        }

        /// <summary>
        /// 查询第一个数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public dynamic QueryFirst(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QueryFirst(sql, param);
            }
        }

        /// <summary>
        /// 查询第一个数据没有返回默认值
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public T QueryFirstOrDefault<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QueryFirstOrDefault<T>(sql, param);
            }
        }

        /// <summary>
        /// 查询第一个数据没有返回默认值
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public dynamic QueryFirstOrDefault(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QueryFirstOrDefault(sql, param);
            }
        }

        /// <summary>
        /// 查询单条数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public T QuerySingle<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QuerySingle<T>(sql, param);
            }
        }

        /// <summary>
        /// 查询单条数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public dynamic QuerySingle(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QuerySingle(sql, param);
            }
        }

        /// <summary>
        /// 查询单条数据没有返回默认值
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public T QuerySingleOrDefault<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QuerySingleOrDefault<T>(sql, param);
            }
        }

        /// <summary>
        /// 查询单条数据没有返回默认值
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public dynamic QuerySingleOrDefault(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.QuerySingleOrDefault(sql, param);
            }
        }

        /// <summary>
        /// 增删改
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public int Execute(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.Execute(sql, param);
            }
        }

        /// <summary>
        /// 根据实体类插入表（实体类需要加标记处理）
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="model"></param>
        /// <param name="transaction"></param>
        /// <param name="commandTimeout"></param>
        /// <returns></returns>
        public async Task<int> InsertAsync<T>(T model, IDbTransaction transaction = null, int? commandTimeout = null) where T : class, new()
        {
            using (DbConnection conn = GetDbConnection())
            {
                return await conn.InsertAsync(model, transaction, commandTimeout);
            }
        }

        /// <summary>
        /// 根据实体类更新表（实体类需要加标记处理）
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="model"></param>
        /// <param name="transaction"></param>
        /// <param name="commandTimeout"></param>
        /// <returns></returns>
        public async Task<bool> UpdateAsync<T>(T model, IDbTransaction transaction = null, int? commandTimeout = null) where T : class, new()
        {
            using (DbConnection conn = GetDbConnection())
            {
                bool b = await conn.UpdateAsync(model, transaction, commandTimeout);
                return b;
            }
        }


        /// <summary>
        /// 根据实体类删除表（实体类需要加标记处理）
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="model"></param>
        /// <param name="transaction"></param>
        /// <param name="commandTimeout"></param>
        /// <returns></returns>
        public async Task<bool> DeleteAsync<T>(T model, IDbTransaction transaction = null, int? commandTimeout = null) where T : class, new()
        {
            using (DbConnection conn = GetDbConnection())
            {
                bool b = await conn.DeleteAsync(model, transaction, commandTimeout);
                return b;
            }
        }

        /// <summary>
        /// Reader获取数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public IDataReader ExecuteReader(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.ExecuteReader(sql, param);
            }
        }

        /// <summary>
        /// Scalar获取数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public object ExecuteScalar(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.ExecuteScalar(sql, param);
            }
        }

        /// <summary>
        /// Scalar获取数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public T ExecuteScalarFor<T>(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.ExecuteScalar<T>(sql, param);
            }
        }

        /// <summary>
        /// Scalar获取数据
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public dynamic ExecuteScalarFor(string sql, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                return con.ExecuteScalar(sql, param);
            }
        }

        /// <summary>
        /// 带参数的存储过程
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public List<T> ExecutePro<T>(string proc, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                List<T> list = con.Query<T>(proc,
                    param,
                    null,
                    true,
                    null,
                    CommandType.StoredProcedure).ToList();
                return list;
            }
        }
        /// <summary>
        /// 带参数的存储过程
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public List<dynamic> ExecutePro(string proc, object param)
        {
            using (IDbConnection con = GetDbConnection())
            {
                List<dynamic> list = con.Query(proc,
                    param,
                    null,
                    true,
                    null,
                    CommandType.StoredProcedure).ToList();
                return list;
            }
        }

        /// <summary>
        /// 事务1 - 全SQL
        /// </summary>
        /// <param name="sqlarr">多条SQL</param>
        /// <param name="param">param</param>
        /// <returns></returns>
        public int ExecuteTransaction<T>(string[] sqlarr)
        {
            using (IDbConnection con = GetDbConnection())
            {
                using (IDbTransaction transaction = con.BeginTransaction())
                {
                    try
                    {
                        int result = 0;
                        foreach (string sql in sqlarr)
                        {
                            result += con.Execute(sql, null, transaction);
                        }

                        transaction.Commit();
                        return result;
                    }
                    catch (Exception)
                    {
                        transaction.Rollback();
                        return 0;
                    }
                }
            }
        }

        /// <summary>
        /// 事务2 - 声明参数
        ///demo:
        ///dic.Add("Insert into Users values (@UserName, @Email, @Address)",
        ///        new { UserName = "jack", Email = "380234234@qq.com", Address = "上海" });
        /// </summary>
        /// <param name="Key">多条SQL</param>
        /// <param name="Value">param</param>
        /// <returns></returns>
        public int ExecuteTransaction<T>(Dictionary<string, object> dic)
        {
            using (IDbConnection con = GetDbConnection())
            {
                using (IDbTransaction transaction = con.BeginTransaction())
                {
                    try
                    {
                        int result = 0;
                        foreach (KeyValuePair<string, object> sql in dic)
                        {
                            result += con.Execute(sql.Key, sql.Value, transaction);
                        }

                        transaction.Commit();
                        return result;
                    }
                    catch (Exception)
                    {
                        transaction.Rollback();
                        return 0;
                    }
                }
            }
        }
    }

使用oracle时候的动态参数需要在替换的变量前使用英文冒号

动态参数

 DapperHelper dapperHelper = new DapperHelper(ConnectTypeEnum.Oracle,
                "Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)))(CONNECT_DATA =(SERVER = test)(SERVICE_NAME = test)));User ID=test;Password=test;");
var data = dapperHelper.Query("select * from Test where ID=:ID", new { ID= "string" });            

DynamicParameters parameters = new DynamicParameters();
            parameters.Add("@ID", "string", System.Data.DbType.String);
DapperHelper dapperHelper = new DapperHelper(ConnectTypeEnum.Oracle,
                "Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)))(CONNECT_DATA =(SERVER = test)(SERVICE_NAME = test)));User ID=test;Password=test;");
var data = dapperHelper.Query("select * from Test where ID=:ID", parameters  });            

//字典转动态参数列表
Dictionary<string, object> dictionary = new Dictionary<string, object>();
            dictionary.Add("@ID", "string");
            var dbArgs = new DynamicParameters(dictionary);
DapperHelper dapperHelper = new DapperHelper(ConnectTypeEnum.Oracle,
                "Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)))(CONNECT_DATA =(SERVER = test)(SERVICE_NAME = test)));User ID=test;Password=test;");
var data = dapperHelper.Query("select * from Test where ID=:ID", dbArgs });          

实体字段映射

新增类

using Dapper;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Reflection;

namespace Test
{

    /// <summary>
    /// Uses the Name value of the <see cref="ColumnAttribute"/> specified to determine
    /// the association between the name of the column in the query results and the member to
    /// which it will be extracted. If no column mapping is present all members are mapped as
    /// usual.
    /// </summary>
    /// <typeparam name="T">The type of the object that this association between the mapper applies to.</typeparam>
    public class ColumnAttributeTypeMapper<T> : FallbackTypeMapper
    {
        public ColumnAttributeTypeMapper()
            : base(new SqlMapper.ITypeMap[]
                {
                    new CustomPropertyTypeMap(
                       typeof(T),
                       (type, columnName) =>
                           type.GetProperties().FirstOrDefault(prop =>
                               prop.GetCustomAttributes(false)
                                   .OfType<ColumnAttribute>()
                                   .Any(attr => attr.Name == columnName)
                               )
                       ),
                    new DefaultTypeMap(typeof(T))
                })
        {
        }
    }


    public class FallbackTypeMapper : SqlMapper.ITypeMap
    {
        private readonly IEnumerable<SqlMapper.ITypeMap> _mappers;

        public FallbackTypeMapper(IEnumerable<SqlMapper.ITypeMap> mappers)
        {
            _mappers = mappers;
        }


        public ConstructorInfo FindConstructor(string[] names, Type[] types)
        {
            foreach (var mapper in _mappers)
            {
                try
                {
                    ConstructorInfo result = mapper.FindConstructor(names, types);
                    if (result != null)
                    {
                        return result;
                    }
                }
                catch (NotImplementedException)
                {
                }
            }
            return null;
        }

        public SqlMapper.IMemberMap GetConstructorParameter(ConstructorInfo constructor, string columnName)
        {
            foreach (var mapper in _mappers)
            {
                try
                {
                    var result = mapper.GetConstructorParameter(constructor, columnName);
                    if (result != null)
                    {
                        return result;
                    }
                }
                catch (NotImplementedException)
                {
                }
            }
            return null;
        }

        public SqlMapper.IMemberMap GetMember(string columnName)
        {
            foreach (var mapper in _mappers)
            {
                try
                {
                    var result = mapper.GetMember(columnName);
                    if (result != null)
                    {
                        return result;
                    }
                }
                catch (NotImplementedException)
                {
                }
            }
            return null;
        }


        public ConstructorInfo FindExplicitConstructor()
        {
            return _mappers
                .Select(mapper => mapper.FindExplicitConstructor())
                .FirstOrDefault(result => result != null);
        }
    }


}

实体上通过Column特性映射字段名

 /// <summary>
    /// 
    /// </summary>
    [Dapper.Contrib.Extensions.Table("Test")]
    public class TestEntity
    {
        [Dapper.Contrib.Extensions.Key]
        [Column("RECORD_ID")]

        public string MyProperty { get; set; }


        [Column( "Field")]
        public string TestField { get; set; }
    }