.net三层结构初探分析第3/4页

using System;
using System.Configuration;

namespace MyCms.DBUtility
{
public class PubConstant
{
public static string ConnectionString
{
get
{
return ConfigurationSettings.AppSettings["ConnectionString"];
}
}
}
}

using System;
using System.Collections;
using System.Text;
using System.Data;
using System.Data.OleDb;

namespace MyCms.DBUtility
{
//数据访问基类(基于OleDb)
public partial class DbHelperOleDb
{
//数据库连接字符串，在web.config中配置
public static string ConnectionString = PubConstant.ConnectionString;
public DbHelperOleDb()
{
}

/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="strSql">SQL语句</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string strSql)
{
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
using (OleDbCommand cmd = new OleDbCommand(strSql, conn))
{
try
{
conn.Open();
return cmd.ExecuteNonQuery();
}
catch(OleDbException E)
{
conn.Close();
throw new Exception(E.Message);
}

}
}
}

/// <summary>
/// 执行多条SQL语句，实现数据库事务
/// </summary>
/// <param name="SqlStrList">多条SQL语句</param>
public static void ExecuteSqlTran(ArrayList SqlStrList)
{
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
conn.Open();
OleDbCommand cmd = new OleDbCommand();
cmd.Connection = conn;
OleDbTransaction tx = conn.BeginTransaction();
cmd.Transaction = tx;
try
{
for (int n = 0; n < SqlStrList.Count; n++)
{
string strSql = SqlStrList[n].ToString();
if (strSql.Trim().Length > 1)
{
cmd.CommandText = strSql;
cmd.ExecuteNonQuery();
}
}
tx.Commit();
}
catch (System.Data.OleDb.OleDbException E)
{
tx.Rollback();
throw new Exception(E.Message);
}
}
}

/// <summary>
/// 执行带一个存储过程参数的SQL语句
/// </summary>
/// <param name="strSql">SQL语句</param>
/// <param name="content">参数内容，比如一个字段是格式复杂的文章</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSinglePro(string strSql, string content)
{
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
OleDbCommand cmd = new OleDbCommand(strSql, conn);
OleDbParameter myParameter = new OleDbParameter("@content",OleDbType.VarChar);
myParameter.Value = content;
cmd.Parameters.Add(myParameter);
try
{
conn.Open();
return cmd.ExecuteNonQuery();
}
catch (OleDbException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}

}
}

/// <summary>
/// 执行一条计算查询结果语句，返回查询结果
/// </summary>
/// <param name="strSql">SQL语句</param>
/// <returns>查询结果</returns>
public static object GetSingle(string strSql)
{
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
using (OleDbCommand cmd = new OleDbCommand(strSql, conn))
{
try
{
conn.Open();
object obj = cmd.ExecuteScalar();
if ((Equals(obj, null)) || Equals(obj, DBNull.Value))
{
return null;
}
else
{
return obj;
}
}
catch (OleDbException E)
{
conn.Close();
throw new Exception(E.Message);
}
}
}
}

/// <summary>
/// 返回OleDbDataReader
/// </summary>
/// <param name="strSql">查询语句</param>
/// <returns>OleDbDataReader</returns>
public static OleDbDataReader ExecuteReader(string strSql)
{
OleDbDataReader dr = null;
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
using(OleDbCommand cmd = new OleDbCommand(strSql,conn))
{
try
{
conn.Open();
cmd.CommandText = strSql;
cmd.CommandType = CommandType.Text;
dr = cmd.ExecuteReader();
}
catch
{
dr.Close();
conn.Close();
cmd.Dispose();
}
}
}
return dr;
}

/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="strSql">查询语句</param>
/// <returns>DataSet</returns>
public static DataSet Query(string strSql)
{
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
DataSet ds = new DataSet();
try
{
conn.Close();
OleDbDataAdapter da = new OleDbDataAdapter(strSql, conn);
da.Fill(ds, "ds");
}
catch (OleDbException E)
{
throw new Exception(E.Message);
}
return ds;
}
}


}
}