C#数据库操作类AccessHelper实例
本文实例讲述了c#数据库操作类accesshelper。分享给大家供大家参考。
具体实现方法如下：
using system.data;
using system.configuration;
using system.data.oledb;
using ahwildlife.utils;
/// <summary>
/// accesshelper 的摘要说明
/// </summary>
public class accesshelper
{
#region 变量
protected static oledbconnection conn = new oledbconnection();
protected static oledbcommand comm = new oledbcommand();
protected static string connectionstring = @"provider=microsoft.jet.oledb.4.0;data source=ahwildlife.mdb;persist security info=false;jet oledb:database password=sa;";
#endregion
#region 构造函数
/// <summary>
/// 构造函数
/// </summary>
public accesshelper()
{
}
#endregion
#region 打开数据库
/// <summary>
/// 打开数据库
/// </summary>
private static void openconnection()
{
if (conn.state == connectionstate.closed)
{
conn.connectionstring = @"provider=microsoft.jet.oledb.4.0;data source=ahwildlife.mdb;persist security info=false;jet oledb:database password=sa;";
comm.connection = conn;
try
{
conn.open();
}
catch (exception ex)
{
throw new exception(ex.message);
}
}
}
#endregion
#region 关闭数据库
/// <summary>
/// 关闭数据库
/// </summary>
private static void closeconnection()
{
if (conn.state == connectionstate.open)
{
conn.close();
conn.dispose();
comm.dispose();
}
}
#endregion
#region 执行sql语句
/// <summary>
/// 执行sql语句
/// </summary>
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();
}
}
#endregion
#region 返回指定sql语句的oledbdatareader对象,使用时请注意关闭这个对象。
/// <summary>
/// 返回指定sql语句的oledbdatareader对象,使用时请注意关闭这个对象。
/// </summary>
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;
}
#endregion
#region 返回指定sql语句的oledbdatareader对象,使用时请注意关闭
/// <summary>
/// 返回指定sql语句的oledbdatareader对象,使用时请注意关闭
/// </summary>
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();
}
}
}
#endregion
#region 返回指定sql语句的dataset
/// <summary>
/// 返回指定sql语句的dataset
/// </summary>
/// <param name="sqlstr"></param>
/// <returns></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 e)
{
throw new exception(e.message);
}
finally
{
closeconnection();
}
return ds;
}
#endregion
#region 返回指定sql语句的dataset
/// <summary>
/// 返回指定sql语句的dataset
/// </summary>
/// <param name="sqlstr"></param>
/// <param name="ds"></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 e)
{
throw new exception(e.message);
}
finally
{
closeconnection();
}
}
#endregion
#region 返回指定sql语句的datatable
/// <summary>
/// 返回指定sql语句的datatable
/// </summary>
/// <param name="sqlstr"></param>
/// <returns></returns>
public static datatable datatable(string sqlstr)
{
datatable dt = common.getdatatablecache(sqlstr);//读缓存
if (dt != null)
{
return dt.copy();
}
else
{
dt = new datatable();
oledbdataadapter da = new oledbdataadapter();
try
{
using (oledbconnection conn = new oledbconnection())
{
conn.connectionstring = connectionstring;
conn.open();
using (oledbcommand comm = new oledbcommand())
{
comm.connection = conn;
comm.commandtype = commandtype.text;
comm.commandtext = sqlstr;
da.selectcommand = comm;
da.fill(dt);
}
}
}
catch (exception e)
{
throw new exception(e.message);
}
finally
{
closeconnection();
}
common.insertdatatablecache(sqlstr, dt);//添加缓存
return dt.copy();
}
}
#endregion
#region 返回指定sql语句的datatable
/// <summary>
/// 返回指定sql语句的datatable
/// </summary>
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 e)
{
throw new exception(e.message);
}
finally
{
closeconnection();
}
}
#endregion
#region 返回指定sql语句的dataview
/// <summary>
/// 返回指定sql语句的dataview
/// </summary>
/// <param name="sqlstr"></param>
/// <returns></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 e)
{
throw new exception(e.message);
}
finally
{
closeconnection();
}
return dv;
}
#endregion
}
希望本文所述对大家的c#程序设计有所帮助。