数据库连接类

/**
* DBHelper 类
* @author OuPay
* @version 1.0 2013/03/03
*/
/// <summary>
/// 数据库连接类
/// </summary>
public class DBHelper
{
private static const string IP = ""; //服务器连接路径
private static const string DB = ""; //数据库名称
private static const string USER = ""; //用户名
private static const string PWD = ""; //密码
public DBHelper(){}
public DBHelper(string IP, string DB, string USER, string PWD)
{
this.IP = IP;
this.DB = DB;
ER = USER;
this.PWD = PWD;
}
//数据库连接语句
private static const string SQL = @"Data Source=" + IP + ";Initial Catalog=" + DB + ";User ID=" + USER + ";Pwd=" + PWD;
//数据库连接对象
private SqlConnection conn;
public SqlConnection Conn
{
get
{
if (conn == null)
{
conn = new SqlConnection(SQL);
}
return conn;
}
}
private SqlCommand comm; //数据库操作对象
/// <summary>
/// 打开数据库
/// </summary>
public void OpenConn()
{
if (Conn.State == ConnectionState.Closed) //数据库是否关闭
{
Conn.Open();
}
else if (Conn.State==ConnectionState.Broken) //数据库重新连接
{
Conn.Close(); //关闭数据库
Conn.Open(); //打开数据库
}
}
/// <summary>
/// 关闭数据库
/// </summary>
public void CloseConn()
{
if (Conn.State == ConnectionState.Open || Conn.State == ConnectionState.Broken) //数据库是否打开或重新连接
{
Conn.Close(); //关闭数据库
}
}
/// <summary>
/// 新增数据
/// </summary>
public static int InsterDB(string sql)
{
int result;
OpenConn(); //打开数据库
comm = new SqlCommand(sql,Conn);
result = comm. ExecuteNonQuery;
CloseConn(); //关闭数据库
return result;
}
/// <summary>
/// 修改数据
/// </summary>
public static int UpdateDB(string sql)
{
int result;
OpenConn(); //打开数据库
comm = new SqlCommand(sql,Conn);
result = comm. ExecuteNonQuery;
CloseConn(); //关闭数据库
return result;
}
/// <summary>
/// 删除数据
/// </summary>
public static int DeleteDB(string sql)
{
int result;
OpenConn(); //打开数据库
comm = new SqlCommand(sql,Conn);
result = comm. ExecuteNonQuery;
CloseConn(); //关闭数据库
return result;
}
/// <summary>
/// 查询数据
/// </summary>
public static SqlDataReader SelectDB(string sql)
{
SqlDataReader sdr = new SqlDataReader();
OpenConn(); //打开数据库
comm = new SqlCommand(sql,Conn);
sdr = comm. Execute Reader();
CloseConn(); //关闭数据库
return sdr;
}
}。