用C#实现的数据库抽象工厂(三)

以下是在应用时真正要调用到的类：

(6)DbAccess.cs

using System;
using System.Data;

namespace DbService
{
/// <summary>
/// DbAccess类,即进行数据库访问时需要调用的类
/// </summary>
public class DbAccess
{
/// <summary>
/// DbAccess构造函数
/// </summary>
public DbAccess()
{
}

/// <summary>
/// 无条件查询操作,即查询表中所有记录
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名组</param>
/// <returns>无条件查询结果</returns>
public static DataSet SelectAll(string strTableName, string[] strColumn)
{
DataSet ds = new DataSet();
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
IDbDataAdapter concreteDbAdapter = abstractDbFactory.CreateDataAdapter();
try
{
string strSql = "SELECT ";
for(int i = 0; i < strColumn.Length - 1; i++)
{
strSql += (strColumn[i] + ", ");
}
strSql += (strColumn[strColumn.Length - 1] + " FROM " + strTableName);
concreteDbCommand.CommandText = strSql;
concreteDbAdapter.SelectCommand = concreteDbCommand;
concreteDbAdapter.Fill(ds);
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
ds.Clear();
throw;
}
finally
{
concreteDbConn.Close();
}
return ds;
}

/// <summary>
/// 条件查询操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名组</param>
/// <param name="strCondition">条件</param>
/// <returns>条件查询结果</returns>
public static DataSet Select(string strTableName, string[] strColumn, string strCondition)
{
DataSet ds = new DataSet();
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
IDbDataAdapter concreteDbAdapter = abstractDbFactory.CreateDataAdapter();
try
{
string strSql = "SELECT ";
for(int i = 0; i < strColumn.Length - 1; i++)
{
strSql += (strColumn[i] + ", ");
}
strSql += (strColumn[strColumn.Length - 1] + " FROM " + strTableName + " WHERE " + strCondition);
concreteDbCommand.CommandText = strSql;
concreteDbAdapter.SelectCommand = concreteDbCommand;
concreteDbAdapter.Fill(ds);
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
ds.Clear();
throw;
}
finally
{
concreteDbConn.Close();
}
return ds;
}

/// <summary>
/// 单条记录的插入操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名组</param>
/// <param name="strValue">值组</param>
public static void Insert(string strTableName, string[] strColumn, object[] strValue)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
string strSql = "INSERT INTO " + strTableName + " (";
for(int i = 0; i < strColumn.Length - 1; i++)
{
strSql += (strColumn[i] + ", ");
}
strSql += (strColumn[strColumn.Length - 1] + ") VALUES ('");
for(int i = 0; i < strValue.Length - 1; i++)
{
strSql += (strValue[i] + "', '");
}
strSql += (strValue[strValue.Length - 1] + "')");
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}
finally
{
concreteDbConn.Close();
}
}

/// <summary>
/// 批量记录的插入操作,即可一次向多张表中插入不同的批量记录
/// </summary>
/// <param name="ds">批量记录组成的DataSet,DataSet中的各个DataTable名为表名,各DataTable中的DataColumn名为列名</param>
public static void InsertSet(ref DataSet ds)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
foreach(DataTable dt in ds.Tables)
{
foreach(DataRow dr in dt.Rows)
{
string strSql = "INSERT INTO " + dt.TableName + " (";
for(int i = 0; i < dt.Columns.Count - 1; i++)
{
strSql += (dt.Columns[i].Caption + ", ");
}
strSql += (dt.Columns[dt.Columns.Count - 1].Caption + ") VALUES ('");
for(int i = 0; i < dt.Columns.Count - 1; i++)
{
strSql += (dr[i] + "', '");
}
strSql += (dr[dt.Columns.Count - 1] + "')");
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
}
}
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}

finally
{
concreteDbConn.Close();
}
}

/// <summary>
/// 无条件删除操作,即删除表中所有记录
/// </summary>
/// <param name="strTableName">表名</param>
public static void DeleteAll(string strTableName)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
string strSql = "DELETE FROM " + strTableName;
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}
finally
{
concreteDbConn.Close();
}
}

/// <summary>
/// 条件删除操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strCondition">条件</param>
public static void Delete(string strTableName, string strCondition)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
string strSql = "DELETE FROM " + strTableName + " WHERE " + strCondition;
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}
finally
{
concreteDbConn.Close();
}
}

/// <summary>
/// 无条件更新操作,即更新表中所有记录
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名组</param>
/// <param name="strValue">值组</param>
public static void UpdateAll(string strTableName, string[] strColumn, object[] strValue)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
string strSql = "UPDATE " + strTableName + " SET ";
for(int i = 0; i < strColumn.Length - 1; i++)
{
strSql += (strColumn[i] + " = '" + strValue[i] + "', ");
}
strSql += (strColumn[strColumn.Length - 1] + " = '" + strValue[strValue.Length - 1] + "' ");
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}
finally
{
concreteDbConn.Close();
}
}

/// <summary>
/// 条件更新操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名组</param>
/// <param name="strValue">值组</param>
/// <param name="strCondition">条件</param>
public static void Update(string strTableName, string[] strColumn, object[] strValue, string strCondition)
{
Factory factory = Factory.GetInstance();
AbstractDbFactory abstractDbFactory = factory.CreateInstance();
IDbConnection concreteDbConn = abstractDbFactory.CreateConnection();
concreteDbConn.ConnectionString = abstractDbFactory.GetConnectionString();
concreteDbConn.Open();
IDbCommand concreteDbCommand = abstractDbFactory.CreateCommand();
IDbTransaction concreteDbTrans = abstractDbFactory.CreateTransaction(concreteDbConn);
concreteDbCommand.Connection = concreteDbConn;
concreteDbCommand.Transaction = concreteDbTrans;
try
{
string strSql = "UPDATE " + strTableName + " SET ";
for(int i = 0; i < strColumn.Length - 1; i++)
{
strSql += (strColumn[i] + " = '" + strValue[i] + "', ");
}
strSql += (strColumn[strColumn.Length - 1] + " = '" + strValue[strValue.Length - 1] + "' " + " WHERE " + strCondition);
concreteDbCommand.CommandText = strSql;
concreteDbCommand.ExecuteNonQuery();
concreteDbTrans.Commit();
}
catch
{
concreteDbTrans.Rollback();
throw;
}
finally
{
concreteDbConn.Close();
}
}
}
}



最后一步，在Web.config中的根结点configuration下增加一些关于数据库连接字符串的变量：

<appSettings>

<add key="DatabaseType" value="SqlServer" />

<add key="SqlServerServer" value="Ricky" />
<add key="SqlServerDatabase" value="test" />
<add key="SqlServerUid" value="sa" />
<add key="SqlServerPwd" value="henhaoba" />

<add key="OleDbProvider" value="Microsoft.jet.oledb.4.0" />
<add key="OleDbDataSource" value="D:\test.mdb" />

<add key="OdbcDriver" value="Microsoft Access Driver (*.mdb)" />
<add key="OdbcDBQ" value="d:\test.mdb" />

</appSettings>




现在一切OK，大家可以通过改变Web.config中的变量来使用不同的数据库连接方式(SqlServer专用连接、OleDb连接和Odbc连接)连接不同的数据库，同时整个使用仍通过DbAccess，不受任何影响。欢迎大家批评指正：）



全文完