一、添加引用

提示：System.Data.OracleClient缺少程序集引用

再把对应路径（例：C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.5.2\System.Data.OracleClient.dll）下的OracleClient.dll文件拷贝到项目的bin文件夹下

二、配置web.config文件

三、在项目根目录下创建Oracle文件夹，并在其中创建OracleHelper.cs文件

using System;using System.Configuration;using System.Collections.Generic;using System.Linq;using System.Web;using System.Data;using System.Data.SqlClient;using System.Data.OracleClient;namespace MyWebService.Oracle{    public class OracleHelper    {        public static OracleConnection GetConn()        {            return new OracleConnection(ConfigurationManager.ConnectionStrings["OracleConnString"].ToString());        }        /// 
        /// 查询操作        /// 
        ///         ///         /// 
            public static DataTable QueryCommand(string querySQL, OracleParameter[] oraParams)        {            DataTable dt = new DataTable();            OracleConnection conn = OracleHelper.GetConn();            OracleCommand cmd = new OracleCommand(querySQL, conn);            if (oraParams != null && oraParams.Length > 0)            {                foreach (OracleParameter oraParam in oraParams)                {                    cmd.Parameters.Add(oraParam);                }            }            OracleDataAdapter adapter = new OracleDataAdapter(cmd);            adapter.Fill(dt);            conn.Close();            return dt;        }    }}

四、引用OracleHelper

创建一个测试类Test.cs

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Data;using System.Data.OracleClient;using MyWebService.Oracle;namespace MyWebService.Test{    public class Test    {        public void TestOracle()        {           //代码块            string querySQL = "SQL语句";            DataTable dt = OracleHelper.QueryCommand(querySQL, null);        }    }}