在C#中利用SharpZipLib进行文件的压缩和解压缩
2024-07-21 02:18:04
供稿：网友
我在做项目的时候需要将文件进行压缩和解压缩，于是就从http://www.icsharpcode.net下载了关于压缩和解压缩的源码，但是下载下来后，面对这么多的代码，一时不知如何下手。只好耐下心来，慢慢的研究，总算找到了门路。针对自己的需要改写了文件压缩和解压缩的两个类，分别为zipclass和unzipclass。其中碰到了不少困难，就决定写出来压缩和解压的程序后，一定把源码贴出来共享，让首次接触压缩和解压缩的朋友可以少走些弯路。下面就来解释如何在c#里用http://www.icsharpcode.net下载的sharpziplib进行文件的压缩和解压缩。
首先需要在项目里引用sharpziplib.dll。然后修改其中的关于压缩和解压缩的类。实现源码如下：
/// <summary>
/// 压缩文件
/// </summary>
using system;
using system.io;
using icsharpcode.sharpziplib.checksums;
using icsharpcode.sharpziplib.zip;
using icsharpcode.sharpziplib.gzip;
namespace compression
{
public class zipclass
{
public void zipfile(string filetozip, string zipedfile ,int compressionlevel, int blocksize)
{
//如果文件没有找到，则报错
if (! system.io.file.exists(filetozip))
{
throw new system.io.filenotfoundexception("the specified file " + filetozip + " could not be found. zipping aborderd");
}
system.io.filestream streamtozip = new system.io.filestream(filetozip,system.io.filemode.open , system.io.fileaccess.read);
system.io.filestream zipfile = system.io.file.create(zipedfile);
zipoutputstream zipstream = new zipoutputstream(zipfile);
zipentry zipentry = new zipentry("zippedfile");
zipstream.putnextentry(zipentry);
zipstream.setlevel(compressionlevel);
byte[] buffer = new byte[blocksize];
system.int32 size =streamtozip.read(buffer,0,buffer.length);
zipstream.write(buffer,0,size);
try
{
while (size < streamtozip.length)
{
int sizeread =streamtozip.read(buffer,0,buffer.length);
zipstream.write(buffer,0,sizeread);
size += sizeread;
}
}
catch(system.exception ex)
{
throw ex;
}
zipstream.finish();
zipstream.close();
streamtozip.close();
}
public void zipfilemain(string[] args)
{
string[] filenames = directory.getfiles(args[0]);
crc32 crc = new crc32();
zipoutputstream s = new zipoutputstream(file.create(args[1]));
s.setlevel(6); // 0 - store only to 9 - means best compression
foreach (string file in filenames)
{
//打开压缩文件
filestream fs = file.openread(file);
byte[] buffer = new byte[fs.length];
fs.read(buffer, 0, buffer.length);
zipentry entry = new zipentry(file);
entry.datetime = datetime.now;
// set size and the crc, because the information
// about the size and crc should be stored in the header
// if it is not set it is automatically written in the footer.
// (in this case size == crc == -1 in the header)
// some zip programs have problems with zip files that don't store
// the size and crc in the header.
entry.size = fs.length;
fs.close();
crc.reset();
crc.update(buffer);
entry.crc = crc.value;
s.putnextentry(entry);
s.write(buffer, 0, buffer.length);
}
s.finish();
s.close();
}
}
}
现在再来看看解压文件类的源码
/// <summary>
/// 解压文件
/// </summary>
using system;
using system.text;
using system.collections;
using system.io;
using system.diagnostics;
using system.runtime.serialization.formatters.binary;
using system.data;
using icsharpcode.sharpziplib.bzip2;
using icsharpcode.sharpziplib.zip;
using icsharpcode.sharpziplib.zip.compression;
using icsharpcode.sharpziplib.zip.compression.streams;
using icsharpcode.sharpziplib.gzip;
namespace decompression
{
public class unzipclass
{
public void unzip(string[] args)
{
zipinputstream s = new zipinputstream(file.openread(args[0]));
zipentry theentry;
while ((theentry = s.getnextentry()) != null)
{
string directoryname = path.getdirectoryname(args[1]);
string filename = path.getfilename(theentry.name);
//生成解压目录
directory.createdirectory(directoryname);
if (filename != string.empty)
{
//解压文件到指定的目录
filestream streamwriter = file.create(args[1]+theentry.name);
int size = 2048;
byte[] data = new byte[2048];
while (true)
{
size = s.read(data, 0, data.length);
if (size > 0)
{
streamwriter.write(data, 0, size);
}
else
{
break;
}
}
streamwriter.close();
}
}
s.close();
}
}
}
有了压缩和解压缩的类以后，就要在窗体里调用了。怎么？是新手，不会调用？ok,接着往下看如何在窗体里调用。
首先在窗体里放置两个命令按钮（不要告诉我你不会放啊~），然后编写以下源码
/// <summary>
/// 调用源码
/// </summary>
private void button2_click_1(object sender, system.eventargs e)
{
string []fileproperties=new string[2];
fileproperties[0]="c://unzipped//";//待压缩文件目录
fileproperties[1]="c://zip//a.zip"; //压缩后的目标文件
zipclass zc=new zipclass();
zc.zipfilemain(fileproperties);
}
private void button2_click(object sender, system.eventargs e)
{
string []fileproperties=new string[2];
fileproperties[0]="c://zip//test.zip";//待解压的文件
fileproperties[1]="c://unzipped//";//解压后放置的目标目录
unzipclass unzc=new unzipclass();
unzc.unzip(fileproperties);
}
好了，到此为止，如何压缩和解压缩的类都已经完成了，需要的朋友直接拿走调吧。
