DotNerCore的ADO.NET操作实例

依赖环境

　　.Net Core 1.0.0-preview2-003121

　　VSCode

一、创建.Net Core项目

　　1、打开命令行选择好工作目录后执行 dotnet new，生成2个文件（Program.cs、project.json）

　　2、执行 dotnet restore 还原整个项目的依赖库 生成相应文件

　　3、执行 dotnet build 编译程序 

　　4、执行 dotnet run 默认输出 helloworld　　

　　此时默认的.net core  console程序已经完成创建 解析依赖 。

二、引用System.Data.SqlClient

　　打开project.json 讲dependencies修改如下

  "dependencies": {
      "System.Data.Common": "4.1.0-*",
      "System.Data.SqlClient" :  "4.1.0-*",
      "System.Runtime": "4.1.0-*"
  },

　　然后执行 dotnet restore ，执行完成后就可以在程序中使用ado.net对象了

　　经编码发现 SqlConnection和SqlCommand都在，查询数据库SqlDataReader保留下来了，但是SqlDataAdapter没有了，所以需要自己创建。

　　另外Datable和DataSet目前仍然不可用所以需要自己创建。因此需要创建三个大类和一些小类（DataRow，DataColumn）

　　搜索了下资料在园友处找到了先造轮子的人孙凯旋 于是拷贝了他的扩展代码整合 DataTableExtensions文件，代码如下

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Threading.Tasks;

namespace SqlSugar
{
    /// <summary>
    /// 作者：sunkaixuan 
    /// 创建时间：2016/7/31
    /// 修改时间：-
    /// 说明：让.netCore支持DataSet
    /// </summary>
    public class DataSet
    {
        /// <summary>
        /// 数据表
        /// </summary>
        public List<DataTable> Tables = new List<DataTable>();
    }

    /// <summary>
    /// 作者：sunkaixuan 
    /// 创建时间：2016/7/31
    /// 修改时间：-
    /// 说明：让.netCore支持DataTable
    /// </summary>
    public class DataTable
    {
        /// <summary>
        /// 列信息
        /// </summary>
        public DataColumnCollection Columns = new DataColumnCollection();
        /// <summary>
        /// 行信息
        /// </summary>
        public DataRowCollection Rows = new DataRowCollection();
    }
    /// <summary>
    /// 数据列
    /// </summary>
    public class DataColumn
    {
        /// <summary>
        /// Data Column
        /// </summary>
        public DataColumn()
        {

        }
        /// <summary>
        /// Column Name
        /// </summary>
        /// <param name="columnName"></param>
        public DataColumn(string columnName)
        {
            this.ColumnName = columnName;
        }
        /// <summary>
        /// Data Column
        /// </summary>
        /// <param name="columnName"></param>
        /// <param name="dataType"></param>
        public DataColumn(string columnName, Type dataType)
        {
            this.ColumnName = columnName;
            this.DataType = dataType;
        }
        /// <summary>
        /// Column Name
        /// </summary>
        public string ColumnName { get; internal set; }
        /// <summary>
        /// Data Type
        /// </summary>
        public Type DataType { get; internal set; }
    }
    /// <summary>
    /// 数据列集合
    /// </summary>
    public class DataColumnCollection : IEnumerable, ICollection, IEnumerator
    {
        /// <summary>
        /// Get Item By Index
        /// </summary>
        /// <param name="thisIndex"></param>
        /// <returns></returns>
        public DataColumn this[int thisIndex]
        {
            get
            {
                return cols[thisIndex];
            }
        }
        private int index = -1;
        private List<DataColumn> cols;
        /// <summary>
        /// Count
        /// </summary>
        public int Count
        {
            get
            {
                if (this.cols == null)
                {
                    this.cols = new List<DataColumn>();
                }
                return this.cols.Count;
            }
        }
        /// <summary>
        /// Add
        /// </summary>
        /// <param name="col"></param>
        public void Add(DataColumn col)
        {
            if (this.cols == null)
            {
                this.cols = new List<DataColumn>();
            }
            this.cols.Add(col);
        }
        /// <summary>
        /// Is Synchronized
        /// </summary>
        public bool IsSynchronized
        {
            get
            {
                return true;
            }
        }
        /// <summary>
        /// Sync Root
        /// </summary>
        public object SyncRoot
        {
            get
            {
                return null;
            }
        }
        /// <summary>
        /// Current
        /// </summary>
        public object Current
        {
            get
            {
                return cols[index];
            }
        }
        /// <summary>
        /// Copy To
        /// </summary>
        /// <param name="array"></param>
        /// <param name="index"></param>
        public void CopyTo(Array array, int index)
        {
            throw new NotImplementedException();
        }

        /// <summary>
        /// 获取该集合的 System.Collections.IEnumerator
        /// </summary>
        /// <returns></returns>
        public IEnumerator GetEnumerator()
        {
            return (IEnumerator)this; ;
        }
        /// <summary>
        /// Move Next
        /// </summary>
        /// <returns></returns>
        public bool MoveNext()
        {
            index++;
            var isNext = index < cols.Count;
            if (!isNext)
                Reset();
            return isNext;
        }
        /// <summary>
        /// Reset
        /// </summary>

        public void Reset()
        {
            index = -1;
        }
        /// <summary>
        /// Contains Key
        /// </summary>
        /// <param name="name"></param>
        /// <returns></returns>

        public bool ContainsKey(string name)
        {
            if (this.cols == null) return false;
            return (this.cols.Any(it => it.ColumnName == name));
        }
    }
    /// <summary>
    /// 数据行集合
    /// </summary>
    public class DataRowCollection : IEnumerable, ICollection, IEnumerator
    {
        /// <summary>
        /// Get item by index
        /// </summary>
        /// <param name="thisIndex"></param>
        /// <returns></returns>
        public DataRow this[int thisIndex]
        {
            get
            {
                return Rows[thisIndex];
            }
        }

        private int index = -1;
        private List<DataRow> Rows = null;
        /// <summary>
        /// Count
        /// </summary>
        public int Count
        {
            get
            {
                if (this.Rows == null)
                {
                    this.Rows = new List<DataRow>();
                }
                return Rows.Count;
            }
        }

        /// <summary>
        /// Current
        /// </summary>
        public object Current
        {
            get
            {
                if (this.Rows == null)
                {
                    this.Rows = new List<DataRow>();
                }
                return Rows[index];
            }
        }
        /// <summary>
        /// Is Synchronized
        /// </summary>
        public bool IsSynchronized
        {
            get
            {
                return true;
            }
        }
        /// <summary>
        /// Sync Root
        /// </summary>
        public object SyncRoot
        {
            get
            {
                return null;
            }
        }
        /// <summary>
        /// Copy To
        /// </summary>
        /// <param name="array"></param>
        /// <param name="index"></param>
        public void CopyTo(Array array, int index)
        {
            throw new NotImplementedException();
        }

        /// <summary>
        /// 获取该集合的 System.Collections.IEnumerator。
        /// </summary>
        /// <returns></returns>
        public IEnumerator GetEnumerator()
        {
            return (IEnumerator)this; ;
        }

        /// <summary>
        /// Move Next
        /// </summary>
        /// <returns></returns>
        public bool MoveNext()
        {
            index++;
            var isNext = index < (Rows==null?0:Rows.Count);
            if (!isNext)
                Reset();
            return isNext;
        }

        /// <summary>
        /// Reset
        /// </summary>
        public void Reset()
        {
            index = -1;
        }

        /// <summary>
        /// Add
        /// </summary>
        /// <param name="daRow"></param>
        internal void Add(DataRow daRow)
        {
            if (Rows == null)
            {
                Rows = new List<DataRow>();
            }
            Rows.Add(daRow);
        }
    }
    /// <summary>
    /// 数据行
    /// </summary>

    public class DataRow
    {
        private Dictionary<string, object> obj = new Dictionary<string, object>();

        /// <summary>
        /// Add
        /// </summary>
        /// <param name="key"></param>
        /// <param name="value"></param>
        public void Add(string key, object value)
        {
            obj.Add(key, value);
        }

        /// <summary>
        /// Get Item  By Name
        /// </summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public object this[string name]
        {
            get
            {
                return obj[name];
            }
        }

        /// <summary>
        /// Get Item By Index
        /// </summary>
        /// <param name="index"></param>
        /// <returns></returns>
        public object this[int index]
        {
            get
            {
                int i = 0;
                object reval = null;
                foreach (var item in obj)
                {
                    if (i == index)
                    {
                        reval = item.Value;
                        break;
                    }
                    i++;
                }
                return reval;
            }
        }

        /// <summary>
        /// Contains Key
        /// </summary>
        /// <param name="columnName"></param>
        /// <returns></returns>
        public bool ContainsKey(string columnName)
        {
            if (this.obj == null) return false;
            return (this.obj.ContainsKey(columnName));
        }
    }
    /// <summary>
    /// 数据填充器
    /// </summary>
    public class SqlDataAdapter
    {
        private SqlCommand command;
        private string sql;
        private SqlConnection _sqlConnection;

        /// <summary>
        /// SqlDataAdapter
        /// </summary>
        /// <param name="command"></param>
        public SqlDataAdapter(SqlCommand command)
        {
            this.command = command;
        }

        /// <summary>
        /// SqlDataAdapter
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="_sqlConnection"></param>
        public SqlDataAdapter(string sql, SqlConnection _sqlConnection)
        {
            this.sql = sql;
            this._sqlConnection = _sqlConnection;
        }

        /// <summary>
        /// SelectCommand
        /// </summary>
        public SqlCommand SelectCommand
        {
            get
            {
                if (this.command == null)
                {
                    this.command = new SqlCommand(this.sql, this._sqlConnection);
                }
                return this.command;
            }
        }

        /// <summary>
        /// Fill
        /// </summary>
        /// <param name="dt"></param>
        public void Fill(DataTable dt)
        {
            if (dt == null)
            {
                dt = new DataTable();
            }
            var columns = dt.Columns;
            var rows = dt.Rows;
            using (SqlDataReader dr = command.ExecuteReader())
            {
                for (int i = 0; i < dr.FieldCount; i++)
                {
                    string name = dr.GetName(i).Trim();
                    if (!columns.ContainsKey(name))
                        columns.Add(new DataColumn(name, dr.GetFieldType(i)));
                }

                while (dr.Read())
                {
                    DataRow daRow = new DataRow();
                    for (int i = 0; i < columns.Count; i++)
                    {
                        if (!daRow.ContainsKey(columns[i].ColumnName))
                            daRow.Add(columns[i].ColumnName, dr.GetValue(i));
                    }
                    dt.Rows.Add(daRow);
                }
            }

        }

        /// <summary>
        /// Fill
        /// </summary>
        /// <param name="ds"></param>
        public void Fill(DataSet ds)
        {
            if (ds == null) {
                ds = new DataSet();
            }
            using (SqlDataReader dr = command.ExecuteReader())
            {
                do
                {
                    var dt = new DataTable();
                    var columns = dt.Columns;
                    var rows = dt.Rows;
                    for (int i = 0; i < dr.FieldCount; i++)
                    {
                        string name = dr.GetName(i).Trim();
                        if (!columns.ContainsKey(name))
                            columns.Add(new DataColumn(name, dr.GetFieldType(i)));
                    }

                    while (dr.Read())
                    {
                        DataRow daRow = new DataRow();
                        for (int i = 0; i < columns.Count; i++)
                        {
                            if (!daRow.ContainsKey(columns[i].ColumnName))
                                daRow.Add(columns[i].ColumnName, dr.GetValue(i));
                        }
                        dt.Rows.Add(daRow);
                    }
                    ds.Tables.Add(dt);
                } while (dr.NextResult());
            }
        }
    }
}

因为要早同个命名空间下才能使用所以需要修改命名空间一致

于是简单的.Net Core ADO.NET查询方法就可以执行了，修改program.cs文件代码如下

using System;
using System.Data;
using System.Data.SqlClient;

namespace ConsoleApplication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            
            string ConStr = 
                "Data Source=.;Initial Catalog=ForTest;Persist Security Info=False;User ID=sa;Password=sa;";
            string CmdStr = 
                "select * from IisLog";

            DataTable dt = new DataTable(); 
            using(SqlConnection con = new SqlConnection(ConStr))
            {
                using(SqlCommand command = new SqlCommand(CmdStr,con))
                {
                    if (con.State != ConnectionState.Open) con.Open();
                    SqlDataAdapter sda = new SqlDataAdapter(command);
                    
                    sda.Fill(dt);
                    
                }
                
            }
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    Console.Write(dt.Rows[i][j] +" ");
                }
                Console.WriteLine();
            }
            
            Console.ReadKey();
        }
        
    }
}

控制台输出了结果