好些日子沒整理自己的筆記了，實在是自己太忙了。我知道著不是借口，真是很累，根本就沒有時間精力去整理這些筆記，現在稍微有點時間，我趕快整理一下思路。我想了想，今天還是把一些基本的類整理一下吧，這些都是我們在平常開發中經常見到的。這些內容，我自己感覺會有些毛病，希望大家幫忙改進一下，謝謝。
一、數據訪問類DataAccess
數據訪問類是我這個小軟件最基礎的類，它主要完成的功能就是，實現了對Access數據庫的訪問操作，具體代碼如下。
using System.Data.OleDb;
using System.Data;
using System;
namespace Common
{
public class DataAccess
{
protected static OleDbConnection conn = new OleDbConnection();
protected static OleDbCommand comm = new OleDbCommand();
public static string connstring = "";
public DataAccess()
{
}
private static void openConnection()
{
if (conn.State == ConnectionState.Closed)
{
conn.ConnectionString = @"Provider=Microsoft.Jet.OleDb.4.0;Data Source=" + connstring;
comm.Connection = conn;
try
{
conn.Open();
}
catch (Exception e)
{ throw new Exception(e.Message); }
}
}
private static void closeConnection()
{
if (conn.State == ConnectionState.Open)
{
conn.Close();
conn.Dispose();
comm.Dispose();
}
}
public static void excuteSql(string sqlstr)
{
try
{
openConnection();
comm.CommandType = CommandType.Text;
comm.CommandText = sqlstr;
comm.ExecuteNonQuery();
}
catch (Exception e)
{
throw new Exception(e.Message);
}
finally
{ closeConnection(); }
}//執行sql語句
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;
}//返回指定sql語句的OleDbDataReader對象，使用時請注意關閉這個對象。
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();
}
}
}//返回指定sql語句的OleDbDataReader對象,使用時請注意關閉
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;
}//返回指定sql語句的dataset
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();
}
}//返回指定sql語句的dataset
public static DataTable dataTable(string sqlstr)
{
DataTable dt = new DataTable();
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();
}
return dt;
}//返回指定sql語句的datatable www.2cto.com
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();
}
}//返回指定sql語句的datatable
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;
}
}
}
這個類也許代碼會有很多問題，請大家幫忙指正。
作者 zhaoyang
