前言
在网络情况不够良好或者网速受限情况下，传输文件时，一般考虑使用压缩算法对文件进行压缩。7z压缩是一个压缩率比较高的软件，我们可以通过他来处理我们的文件。主要有两种方式进行压缩：方式1，直接通过调用库方式，可以在网上找到他的库算法；方式2，通过CMD命令行模式调用。
1、直接调用库
直接调用库，有一个好处是后期可控制性比较好，它还提供了一个处理回调函数。可以查看处理情况。但传递参数较多，需要好好研究研究。
//文件压缩处理
private void ProcessFileEncode(string inputName, string outputName)
{
Stream inStream = new FileStream(inputName, FileMode.Open, FileAccess.Read);
FileStream outStream = new FileStream(outputName, FileMode.Create, FileAccess.Write);
FileStream trainStream = null;
Int32 dictionary = 1 << 23;
Int32 posStateBits = 2;
Int32 litContextBits = 3;
Int32 litPosBits = 0;
Int32 algorithm = 2;
Int32 numFastBytes = 128;
bool eos = true;
CoderPropID[] propIDs =
{
CoderPropID.DictionarySize,
CoderPropID.PosStateBits,
CoderPropID.LitContextBits,
CoderPropID.LitPosBits,
CoderPropID.Algorithm,
CoderPropID.NumFastBytes,
CoderPropID.MatchFinder,
CoderPropID.EndMarker
};
object[] properties =
{
dictionary,
posStateBits,
litContextBits,
litPosBits,
algorithm,
numFastBytes,
"bt4",
eos
};
Encoder encoder = new Encoder();
encoder.SetCoderProperties(propIDs, properties);
encoder.WriteCoderProperties(outStream);
Int64 fileSize = inStream.Length;
for (int i = 0; i < 8; i++)
outStream.WriteByte((Byte)(fileSize >> (8 * i)));
if (trainStream != null)
{
CDoubleStream doubleStream = new CDoubleStream();
doubleStream.s1 = trainStream;
doubleStream.s2 = inStream;
doubleStream.fileIndex = 0;
inStream = doubleStream;
long trainFileSize = trainStream.Length;
doubleStream.skipSize = 0;
if (trainFileSize > dictionary)
doubleStream.skipSize = trainFileSize - dictionary;
trainStream.Seek(doubleStream.skipSize, SeekOrigin.Begin);
encoder.SetTrainSize((uint)(trainFileSize - doubleStream.skipSize));
}
encoder.Code(inStream, outStream, -1, -1, proceCallInfo);
outStream.Close();
inStream.Close();
}
//文件解压处理
private void ProcessFileDecode(string inputName, string outputName)
{
Stream inStream = new FileStream(inputName, FileMode.Open, FileAccess.Read);
FileStream outStream = new FileStream(outputName, FileMode.Create, FileAccess.Write);
byte[] properties = new byte[5];
if (inStream.Read(properties, 0, 5) != 5)
throw new Exception("input .lzma is too short");
Decoder decoder = new Decoder();
decoder.SetDecoderProperties(properties);
long outSize = 0;
for (int i = 0; i < 8; i++)
{
int v = inStream.ReadByte();
if (v < 0)
throw new Exception("Can't Read 1");
outSize |= ((long)(byte)v) << (8 * i);
}
long compressedSize = inStream.Length - inStream.Position;
decoder.Code(inStream, outStream, compressedSize, outSize, proceCallInfo);
outStream.Close();
inStream.Close();
}处理信息
public class ProceCallInfo : BindableBase, ICodeProgress
{
private long inSize;
public long InSize
{
get { return inSize; }
set { Set(ref inSize, value); }
}
private long outSize;
public long OutSize
{
get { return outSize; }
set { Set(ref outSize, value); OnPropertyChanged("Ration"); }
}
private string processRatio;
public string ProcessRatio
{
get { return processRatio; }
set { Set(ref processRatio, value); }
}
public double Ration
{
get
{
if (outSize == 0 || InSize == 0)
return 0;
else
return outSize * 1.0 / InSize;
}
}
public void SetProgress(long inSize, long outSize)
{
InSize = inSize;
OutSize = outSize;
}
}
2、CMD间接方式
/// <summary>
/// 压缩文件
/// </summary>
/// <param name="strInFilePath">指定需要压缩的文件，如C:\test\demo.xlsx，将压缩demo.xlsx文件</param>
/// <param name="strOutFilePath">压缩后压缩文件的存放目录</param>
public void CompressFile(string strInFilePath, string strOutFilePath)
{
Process process = new Process();
process.StartInfo.FileName = this._7zInstallPath;
process.StartInfo.Arguments = " a -t7z " + strOutFilePath + " " + strInFilePath + "";
//隐藏DOS窗口
process.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
process.Start();
process.WaitForExit();
process.Close();
}
/// <summary>
/// 解压缩
/// </summary>
/// <param name="strInFilePath">压缩文件的路径</param>
/// <param name="strOutDirectoryPath">解压缩后文件的路径</param>
public void DecompressFileToDestDirectory(string strInFilePath, string strOutDirectoryPath)
{
Process process = new Process();
process.StartInfo.FileName = this._7zInstallPath;
process.StartInfo.Arguments = " x " + strInFilePath + " -o" + strOutDirectoryPath + " -r ";
//隐藏DOS窗口
process.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
process.Start();
process.WaitForExit();
process.Close();
}3、主调逻辑
压缩文件
//压缩文件
private async void Button_Click_1(object sender, RoutedEventArgs e)
{
string OrgfilePath = @"D:\图像\123.tiff";
string outfilePath = @"D:\图像\777.7z";
WriteInfo("start Process!");
Button btn = sender as Button;
btn.IsEnabled = false;
stopwatch.Restart();
string path = @"C:\Program Files\7-Zip\7zg.exe";
ZipHelper zipHelper = new ZipHelper(path);
await Task.Run(() =>
{
// zipHelper.CompressFile(OrgfilePath,outfilePath);
ProcessFileEncode(OrgfilePath, outfilePath);
});
stopwatch.Stop();
WriteInfo($"End Process {stopwatch.ElapsedMilliseconds}ms!");
btn.IsEnabled = true;
}解压文件
private async void Button_Click_2(object sender, RoutedEventArgs e)
{
string OrgfilePath = @"D:\图像\777.7z";
string outfilePath = @"D:\图像\777.tiff";
WriteInfo("start Process!");
Button btn = sender as Button;
btn.IsEnabled = false;
stopwatch.Restart();
await Task.Run(() =>
{
// zipHelper.CompressDirectory(OrgfilePath, outfilePath);
ProcessFileDecode(OrgfilePath, outfilePath);
});
stopwatch.Stop();
WriteInfo($"End Process {stopwatch.ElapsedMilliseconds}ms!");
btn.IsEnabled = true;
}