用C#實現的數據庫抽象工廠(三)

以下是在應用時真正要調用到的類：

(6)DbAccess.cs

using System;
using System.Data;

namespace DbService
{
/// <summary>
/// DbAccess類,即進行數據庫訪問時需要調用的類
/// </summary>
public class DbAccess
{
/// <summary>
/// DbAccess構造函數
/// </summary>
public DbAccess()
{
}

/// <summary>
/// 無條件查詢操作,即查詢表中所有記錄
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名組</param>
/// <returns>無條件查詢結果</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>
/// 條件查詢操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名組</param>
/// <param name="strCondition">條件</param>
/// <returns>條件查詢結果</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>
/// 單條記錄的插入操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名組</param>
/// <param name="strValue">值組</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>
/// 批量記錄的插入操作,即可一次向多張表中插入不同的批量記錄
/// </summary>
/// <param name="ds">批量記錄組成的DataSet,DataSet中的各個DataTable名為表名,各DataTable中的DataColumn名為列名</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>
/// 無條件刪除操作,即刪除表中所有記錄
/// </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>
/// 條件刪除操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strCondition">條件</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>
/// 無條件更新操作,即更新表中所有記錄
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名組</param>
/// <param name="strValue">值組</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>
/// 條件更新操作
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColumn">列名組</param>
/// <param name="strValue">值組</param>
/// <param name="strCondition">條件</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中的根結點configuration下增加一些關于數據庫連接字符串的變量：

<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>




現在一切OK，大家可以通過改變Web.config中的變量來使用不同的數據庫連接方式(SqlServer專用連接、OleDb連接和Odbc連接)連接不同的數據庫，同時整個使用仍通過DbAccess，不受任何影響。歡迎大家批評指正：）



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