C# 连接 Oracle 数据库（三种方式：OracleClient、ODBC、OLEDB）

1、OracleClient
//基于.NET 2.0，只有2.0中包含OracleClient
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Security.Cryptography;
using System.IO;
using System.Collections.Generic;
using System.Configuration;
using System.Data.SqlClient;
using System.Data.OracleClient;
public partial class orclService : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Response.AddHeader("Access-Control-Allow-Origin", "*");
List<info> result = new List<info>();
string callback = Request.QueryString["method"];
if (callback == "getTableInfo")
result = getTableInfo();
Response.Write(result);
Response.End();
}

//<add key="orclCon" value="Data Source=ORCL;User Id=sa;Password=123;"/>
private static string strConn = ConfigurationSettings.AppSettings["orclCon"];

[WebMethod(Description = "<h3>Oracle连接测试</h3>")]
public List<info> getTableInfo()
{
List<info> list = new List<info>();

OracleConnection conn = new OracleConnection(strConn);
conn.Open();
string strComm = "select * from ATEST_POLYGON";
OracleCommand comm = new OracleCommand(strComm, conn);
OracleDataReader sdr = comm.ExecuteReader();
info strInfo = null;

while (sdr.Read())
{
strInfo = new info();
strInfo.ID = sdr["ID"].ToString();
strInfo.Content = sdr["CONTENT"].ToString();
list.Add(strInfo);
}

if (!sdr.HasRows)
{
strInfo.Content = "无匹配记录";
list.Add(strInfo);
}

sdr.Close();
return list;
}

public class info
{
private string id;
public string ID
{
get { return this.id; }
set { this.id = value; }
}
private string content;
public string Content
{
get { return this.content; }
set { this.content = value; }
}
}

}
2、ODBC（参见“Oracle 通过 ODBC 连接”）
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;
using System.Security.Cryptography;
using System.IO;
using System.Collections.Generic;
using System.Configuration;
using System.Data.SqlClient;
using System.Data.Odbc;
public partial class orclService : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Response.AddHeader("Access-Control-Allow-Origin", "*");
int result = 0;
string callback = Request.QueryString["method"];
if (callback == "getTableInfo")
result = getTableInfo();
Response.Write(result);
Response.End();
}

//<add key="orclCon_windows" value="DSN=oracle_windows;UID=sa;PWD=123;"/>
// <add key="orclCon_linux" value="DSN=oracle_linux;UID=sde;PWD=sde;"/>
private static string strConn = ConfigurationSettings.AppSettings["orclCon_linux"];

[WebMethod(Description = "<h3>Oracle连接测试</h3>")]
public int getTableInfo()
{
OdbcConnection odbcconn = new OdbcConnection(strConn);
odbcconn.Open();
string strComm = "select * from ATEST_POLYGON";
OdbcDataAdapter odbcda = new OdbcDataAdapter(strComm, odbcconn);
DataSet ds = new DataSet();
odbcda.Fill(ds);
DataTable dt = new DataTable();
dt = ds.Tables[0];
odbcconn.Close();
odbcconn.Dispose();
return dt.Rows.Count;
}
}
3、OLEDB
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;
using System.Security.Cryptography;
using System.IO;
using System.Collections.Generic;
using System.Configuration;
using System.Data.SqlClient;
using System.Data.OleDb;
public partial class orclService : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Response.AddHeader("Access-Control-Allow-Origin", "*");
List<info> result = new List<info>();
string callback = Request.QueryString["method"];
if (callback == "getTableInfo")
result = getTableInfo();
Response.Write(result);
Response.End();
}

//<add key="orclCon_windows" value="Provider=OraOLEDB.Oracle.1;Data Source=ORCL;User ID=sa;Password=123;Persist Security Info=False;"/>
//<add key="orclCon_linux" value="Provider=OraOLEDB.Oracle.1;Data Source=ORCL_LINUX;User ID=sde;Password=sde;Persist Security Info=False;"/>
private static string strConn = ConfigurationSettings.AppSettings["orclCon_windows"];

[WebMethod(Description = "<h3>Oracle连接测试</h3>")]
public List<info> getTableInfo()
{
List<info> list = new List<info>();

OleDbConnection conn = new OleDbConnection(strConn);
conn.Open();
string strComm = "select * from ATEST_POLYGON";
OleDbCommand comm = new OleDbCommand(strComm, conn);
OleDbDataReader sdr = comm.ExecuteReader();
info strInfo = null;

while (sdr.Read())
{
strInfo = new info();
strInfo.ID = sdr["ID"].ToString();
strInfo.Content = sdr["CONTENT"].ToString();
list.Add(strInfo);
}

if (!sdr.HasRows)
{
strInfo.Content = "无匹配记录";
list.Add(strInfo);
}

sdr.Close();
return list;
conn.Close();
conn.Dispose();
return list;
}

public class info
{
private string id;
public string ID
{
get { return this.id; }
set { this.id = value; }
}
private string content;
public string Content
{
get { return this.content; }
set { this.content = value; }
}
}
}