using System;
using System.Data;
using System.Data.OleDb;
using System.Web;
namespace SysClassLibrary
{
/// <summary>
/// DataAccess 数据访问类
/// <description>数据处理基类,调用方式：DataAccess.DataSet((string)sqlstr);或者DataAccess.DataSet((string)sqlstr,ref DataSet ds); </description>
/// </summary>
public class DataAccess
{
#region 属性
protected static OleDbConnection conn = new OleDbConnection();
protected static OleDbCommand comm = new OleDbCommand();
#endregion
public DataAccess()
{
//init();
}
#region 内部函数 静态方法中不会执行DataAccess()构造函数
/// <summary>
/// 打开数据库连接
/// </summary>
private static void openConnection()
{
if (conn.State == ConnectionState.Closed)
{
//SysConfig.ConnectionString 为系统配置类中连接字符串
string strDbName = HttpContext.Current.Server.MapPath(@"~/App_Data/BookShop.mdb");
conn.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strDbName;
comm.Connection = conn;
try
{
conn.Open();
}
catch (Exception e)
{
throw new Exception(e.Message);
}
}
}
/// <summary>
/// 关闭当前数据库连接
/// </summary>
private static void closeConnection()
{
if (conn.State == ConnectionState.Open)
conn.Close();
conn.Dispose();
comm.Dispose();
}
#endregion
/// <summary>
/// 执行Sql查询语句
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
public static void ExecuteSql(string sqlstr)
{
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
comm.ExecuteNonQuery();
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
}
/// <summary>
/// 执行Sql查询语句并返回第一行的第一条记录,返回值为object 使用时需要拆箱操作 -> Unbox
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <returns>object 返回值 </returns>
public static object ExecuteScalar(string sqlstr)
{
object obj = new object();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
obj = comm.ExecuteScalar();
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
return obj;
}
/// <summary>
/// 执行Sql查询语句,同时进行事务处理
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
public static void ExecuteSqlWithTransaction(string sqlstr)
{
closeConnection();
openConnection();
OleDbTransaction trans;
trans = conn.BeginTransaction();
comm.Transaction = trans;
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
comm.ExecuteNonQuery();
trans.Commit();
}
catch
{
trans.Rollback();
}
finally
{
closeConnection();
}
}
/// <summary>
/// 返回指定Sql语句的OleDbDataReader，请注意，在使用后请关闭本对象，同时将自动调用closeConnection()来关闭数据库连接
/// 方法关闭数据库连接
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <returns>OleDbDataReader对象</returns>
public static OleDbDataReader DataReader(string sqlstr)
{
OleDbDataReader dr = null;
try
{
openConnection();
comm.CommandText = sqlstr;
comm.CommandType = CommandType.Text;
dr = comm.ExecuteReader(CommandBehavior.CloseConnection);
}
catch
{
try
{
dr.Close();
closeConnection();
}
catch
{
}
}
return dr;
}
/// <summary>
/// 返回指定Sql语句的OleDbDataReader，请注意，在使用后请关闭本对象，同时将自动调用closeConnection()来关闭数据库连接
/// 方法关闭数据库连接
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <param name="dr">传入的ref DataReader 对象</param>
public static void DataReader(string sqlstr, ref OleDbDataReader dr)
{
try
{
openConnection();
comm.CommandText = sqlstr;
comm.CommandType = CommandType.Text;
dr = comm.ExecuteReader(CommandBehavior.CloseConnection);
}
catch
{
try
{
if (dr != null && !dr.IsClosed)
dr.Close();
}
catch
{
}
finally
{
closeConnection();
}
}
}
/// <summary>
/// 返回指定Sql语句的DataSet
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <returns>DataSet</returns>
public static DataSet DataSet(string sqlstr)
{
DataSet ds = new DataSet();
OleDbDataAdapter da = new OleDbDataAdapter();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
da.SelectCommand = comm;
da.Fill(ds);
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
return ds;
}
/// <summary>
/// 返回指定Sql语句的DataSet
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <param name="ds">传入的引用DataSet对象</param>
public static void DataSet(string sqlstr, ref DataSet ds)
{
OleDbDataAdapter da = new OleDbDataAdapter();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
da.SelectCommand = comm;
da.Fill(ds);
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
}
/// <summary>
/// 返回指定Sql语句的DataTable
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <returns>DataTable</returns>
public static DataTable DataTable(string sqlstr)
{
OleDbDataAdapter da = new OleDbDataAdapter();
DataTable Datatable = new DataTable();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
da.SelectCommand = comm;
da.Fill(Datatable);
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
return Datatable;
}
/// <summary>
/// 执行指定Sql语句,同时给传入DataTable进行赋值
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <param name="dt">ref DataTable dt </param>
public static void DataTable(string sqlstr, ref DataTable dt)
{
OleDbDataAdapter da = new OleDbDataAdapter();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
da.SelectCommand = comm;
da.Fill(dt);
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
}
/// <summary>
/// 返回指定Sql语句的DataView
/// </summary>
/// <param name="sqlstr">传入的Sql语句</param>
/// <returns>DataView</returns>
public static DataView DataView(string sqlstr)
{
OleDbDataAdapter da = new OleDbDataAdapter();
DataView dv = new DataView();
DataSet ds = new DataSet();
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
da.SelectCommand = comm;
da.Fill(ds);
dv = ds.Tables[0].DefaultView;
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
closeConnection();
}
return dv;
}
}
}