/// <summary>
/// 读取
/// </summary>
public static void Read(DatabaseEntity model)
{
model.MasterFile.Database = model;
//读主文件
DataFileManage.Read(model.MasterFile);
//读数据库信息
DataPageEntity modelD = new DataPageEntity { DataFile = model.MasterFile, ID = Config.DATABASE_PAGE_ID };
DataPageManage.Read(modelD);
model.FromBytes(modelD.Content);
}
/// <summary>
/// 删除
/// </summary>
public static void Delete(DataColumnEntity modelDC)
{
//清空列的内容页
long ContentPageID = modelDC.ContentPageID;
while (ContentPageID > 0)
{
DataPageEntity modelDP = new DataPageEntity { DataFile = modelDC.Table.DataFile, ID = ContentPageID };
ContentPageID = DataContentManage.ReadNextPageID(modelDP);
DataPageManage.Clear(modelDP);
}
modelDC.ColumnPage.Columns.Remove(modelDC);
modelDC.Table.UserColumns.Remove(modelDC);
modelDC.ColumnPage.DataPage.Content = modelDC.ColumnPage.ToBytes();
DataPageManage.Write(modelDC.ColumnPage.DataPage);
modelDC = null;
}
/// <summary>
/// 创建文件
/// </summary>
public static void Create(DataFileEntity model)
{
FileStream fs = new FileStream(model.FilePath, FileMode.CreateNew);
model.FileStream = fs;
model.MaxPageID = 2;
//写入0页
DataPageManage.Write(new DataPageEntity { DataFile = model, ID = Config.DATABASE_PAGE_ID, Content = model.Database.ToBytes() });
//写入1页
DataPageManage.Write(new DataPageEntity { DataFile = model, ID = Config.DATAFILE_PAGE_ID, Content = model.ToBytes() });
//写入2页
TablePageEntity modelTP = new TablePageEntity { Tables = new List<DataTable.DataTableEntity>() };
DataPageEntity modelDP= new DataPageEntity { DataFile = model, ID = Config.DATATABLE_PAGE_ID, Content = modelTP.ToBytes() };
DataPageManage.Write(modelDP);
//赋值
modelTP.DataPage = modelDP;
model.TablePage = modelTP;
}
/// <summary>
/// 创建
/// </summary>
public static void Create(DatabaseEntity modelD,DataTableEntity modelDT)
{
modelDT.TablePage = modelD.MasterFile.TablePage;
modelDT.ID = modelD.Tables.Count == 0 ? 1 : modelD.Tables.Max(info => info.ID) + 1;
//列信息编号
modelDT.ColumnPageID = DataFileManage.GetEmptyPageID(modelD.MasterFile);
//写入表
modelDT.TablePage.Tables.Add(modelDT);
modelDT.TablePage.DataPage.Content = modelDT.TablePage.ToBytes();
DataPageManage.Write(modelDT.TablePage.DataPage);
//创建列分页
ColumnPageEntity modelCP = new ColumnPageEntity { Columns = new List<DataColumnEntity>(), Table = modelDT };
DataPageEntity modelDP = new DataPageEntity { DataFile = modelD.MasterFile, ID = modelDT.ColumnPageID ,Content = modelCP.ToBytes()};
DataPageManage.Write(modelDP);
//赋值
modelCP.DataPage = modelDP;
modelDT.ColumnPage = modelCP;
modelDT.UserColumns = new List<DataColumnEntity>();
//创建系统列
DataColumnEntity modelDC = new DataColumnEntity { Name = EColumnType.RowIndex.ToString(), Type = EColumnType.RowIndex, DataType = EContentType.Byte, DataLength = Config.ROWINDEX_LENGTH };
DataColumnManage.Create(modelDT, modelDC);
}
/// <summary>
/// 写下一页编号
/// </summary>
/// <param name="modelDP"></param>
/// <returns></returns>
public static void WriteNextPageID(DataPageEntity modelDP, long NextPageID)
{
modelDP.Content = BitConverter.GetBytes(NextPageID);
DataPageManage.Write(modelDP, ContentPageEntity.NEXTPAGEID_START, sizeof(Int64));
}
/// <summary>
/// 读取下一页编号
/// </summary>
/// <param name="modelDP"></param>
/// <returns></returns>
public static long ReadNextPageID(DataPageEntity modelDP)
{
DataPageManage.Read(modelDP, ContentPageEntity.NEXTPAGEID_START, sizeof(Int64));
return BitConverter.ToInt64(modelDP.Content, 0);
}
/// <summary>
/// 读取内容页
/// </summary>
/// <param name="modelDP"></param>
/// <returns></returns>
public static ContentPageEntity ReadContentPage(DataPageEntity modelDP,ContentPageEntity modelCP)
{
DataPageManage.Read(modelDP);
modelCP.DataPage = modelDP;
modelCP.FromBytes(modelDP.Content);
modelDP.Content = null;
return modelCP;
}
/// <summary>
/// 新建内容页
/// </summary>
/// <param name="modelDC">所在列</param>
/// <param name="PageID">前一页页编号</param>
/// <param name="PageIndex">页号</param>
/// <returns></returns>
public static ContentPageEntity NewContentPage(DataColumnEntity modelDC, long PageID, int PageIndex)
{
long NextPageID = DataFileManage.GetEmptyPageID(modelDC.Table.DataFile);
//修改前一页
WriteNextPageID(new DataPageEntity { DataFile = modelDC.Table.DataFile, ID = PageID }, NextPageID);
//创建数据分页
byte[] array = new byte[Config.PAGE_SIZE];
array[0] = Convert.ToByte(EPageType.DataContent);
DataPageEntity modelDP = new DataPageEntity { DataFile = modelDC.Table.DataFile, ID = NextPageID, Content = array };
DataPageManage.Write(modelDP);
modelDP.Content = null;
//创建实体
ContentPageEntity modelCP = new ContentPageEntity { Column = modelDC, DataPage=modelDP, PageIndex = PageIndex, Contents = new List<DataContentEntity>() };
return modelCP;
}
/// <summary>
/// 读文件
/// </summary>
/// <param name="modelDF"></param>
public static void Read(DataFileEntity model)
{
model.FileStream = new FileStream(model.FilePath, FileMode.Open);
//读文件信息
DataPageEntity modelDP = new DataPageEntity { DataFile = model, ID = Config.DATAFILE_PAGE_ID };
DataPageManage.Read(modelDP);
model.FromBytes(modelDP.Content);
//读表信息
DataPageEntity modelDPT = new DataPageEntity { DataFile = model, ID = Config.DATATABLE_PAGE_ID };
DataPageManage.Read(modelDPT);
model.TablePage = new TablePageEntity();
model.TablePage.DataPage = modelDPT;
model.TablePage.FromBytes(modelDPT.Content);
//读取列
foreach (DataTableEntity modelDT in model.TablePage.Tables)
{
DataPageEntity modelDPTemp = new DataPageEntity { DataFile = model, ID = modelDT.ColumnPageID };
DataPageManage.Read(modelDPTemp);
modelDT.ColumnPage = new ColumnPageEntity();
modelDT.ColumnPage.DataPage = modelDPTemp;
modelDT.ColumnPage.Table = modelDT;
modelDT.ColumnPage.FromBytes(modelDPTemp.Content);
//表用户列
modelDT.UserColumns = new List<DataColumnEntity>();
modelDT.UserColumns.AddRange(modelDT.ColumnPage.Columns.Where(info => info.Type == EColumnType.User));
}
}
/// <summary>
/// 写入
/// </summary>
/// <param name="model">页实体</param>
/// <param name="start">页中起始位置</param>
/// <param name="length">长度</param>
public static void Write(DataPageEntity model,int start=0, int length=Config.PAGE_SIZE)
{
model.DataFile.FileStream.Seek(model.ID * Config.PAGE_SIZE + start, SeekOrigin.Begin);
model.DataFile.FileStream.Write(model.Content, 0, length);
}
/// <summary>
/// 清空页
/// </summary>
/// <param name="model"></param>
public static void Clear(DataPageEntity model)
{
model.Content = new byte[] { Convert.ToByte(EPageType.Empty) };
Write(model, 0, 1);
}
/// <summary>
/// 修改
/// </summary>
public static void Update(DataColumnEntity modelDC,DataColumnEntity newDC)
{
if (modelDC.DataLength!= newDC.DataLength || modelDC.DataType!=newDC.DataType)//改变列类型或长度
{
List<DataContentEntity> listDC = DataContentManage.Read(modelDC, info => true);
//清空列的内容页
long ContentPageID = modelDC.ContentPageID;
while (ContentPageID > 0)
{
DataPageEntity modelDP = new DataPageEntity { DataFile = modelDC.Table.DataFile, ID = ContentPageID };
ContentPageID = DataContentManage.ReadNextPageID(modelDP);
DataPageManage.Clear(modelDP);
}
//创建数据分页
byte[] array = new byte[Config.PAGE_SIZE];
array[0] = Convert.ToByte(EPageType.DataContent);
DataPageManage.Write(new DataPageEntity { DataFile = modelDC.Table.DataFile, ID = modelDC.ContentPageID, Content = array });
//改变列
modelDC.Name = newDC.Name;
modelDC.DataType = newDC.DataType;
modelDC.DataLength = newDC.DataLength;
modelDC.ColumnPage.DataPage.Content = modelDC.ColumnPage.ToBytes();
DataPageManage.Write(modelDC.ColumnPage.DataPage);
//写入数据
for (int i = 0; i < listDC.Count; i++)
{
DataContentManage.Create(modelDC, listDC[i], i);
}
}
else if (modelDC.Name != newDC.Name)//只改变列名
{
modelDC.Name = newDC.Name;
modelDC.ColumnPage.DataPage.Content = modelDC.ColumnPage.ToBytes();
DataPageManage.Write(modelDC.ColumnPage.DataPage);
}
}
