internal void WriteDir(IFormatterX writer)
{
Signature = ZipConstants.ZipDirEntrySignature;
// 写入头部
writer.Write(this);
}
internal void Write(IFormatterX writer)
{
Signature = ZipConstants.ZipEntrySignature;
// 取得数据流位置
RelativeOffsetOfLocalHeader = (UInt32)writer.Stream.Position;
if (IsDirectory)
{
// 写入头部
writer.Write(this);
return;
}
Int32 dsLen = (Int32)DataSource.Length;
//if (dsLen <= 0) CompressionMethod = CompressionMethod.Stored;
// 计算签名和大小
if (Crc == 0)
{
Crc = DataSource.GetCRC();
}
if (UncompressedSize == 0)
{
UncompressedSize = (UInt32)dsLen;
}
if (CompressionMethod == CompressionMethod.Stored)
{
CompressedSize = UncompressedSize;
}
if (DataSource.IsCompressed)
{
CompressedSize = (UInt32)dsLen;
}
// 写入头部
writer.Write(this);
// 没有数据，直接跳过
if (dsLen <= 0)
{
return;
}
#region 写入文件数据
// 数据源。只能用一次，因为GetData的时候把数据流移到了合适位置
var source = DataSource.GetData();
if (DataSource.IsCompressed)
{
// 可能数据源是曾经被压缩过了的，比如刚解压的实体
source.CopyTo(writer.Stream, 0, dsLen);
return;
}
switch (CompressionMethod)
{
case CompressionMethod.Stored:
// 原始数据流直接拷贝到目标。必须指定大小，否则可能读过界
source.CopyTo(writer.Stream, 0, dsLen);
break;
case CompressionMethod.Deflated:
{
// 记录数据流位置，待会用来计算已压缩大小
Int64 p = writer.Stream.Position;
using (var stream = new DeflateStream(writer.Stream, CompressionMode.Compress, true))
{
source.CopyTo(stream);
stream.Close();
}
CompressedSize = (UInt32)(writer.Stream.Position - p);
// 回头重新修正压缩后大小CompressedSize
p = writer.Stream.Position;
// 计算好压缩大小字段所在位置
writer.Stream.Seek(RelativeOffsetOfLocalHeader + 18, SeekOrigin.Begin);
//var wr = writer as IWriter2;
//wr.Write(CompressedSize);
writer.Write(CompressedSize);
writer.Stream.Seek(p, SeekOrigin.Begin);
}
break;
//case CompressionMethod.LZMA:
// {
// // 记录数据流位置，待会用来计算已压缩大小
// Int64 p = writer.Stream.Position;
// source.CompressLzma(writer.Stream, 10);
// CompressedSize = (UInt32)(writer.Stream.Position - p);
// // 回头重新修正压缩后大小CompressedSize
// p = writer.Stream.Position;
// // 计算好压缩大小字段所在位置
// writer.Stream.Seek(RelativeOffsetOfLocalHeader + 18, SeekOrigin.Begin);
// var wr = writer as IWriter2;
// wr.Write(CompressedSize);
// writer.Stream.Seek(p, SeekOrigin.Begin);
// }
// break;
default:
throw new XException("无法处理的压缩算法{0}！", CompressionMethod);
}
//#if DEBUG
// if (ts != null) ts.UseConsole = true;
//#endif
#endregion
}