public static void CreateUncompressedArchive()
{
using (var testStream = new MemoryStream())
{
var testfilename = "testfile";
var testFileContent = "Lorem ipsum dolor sit amet, consectetur adipiscing elit.";
using (var zip = new ZipArchive(testStream, ZipArchiveMode.Create))
{
var utf8WithoutBom = new Text.UTF8Encoding(encoderShouldEmitUTF8Identifier: false);
ZipArchiveEntry newEntry = zip.CreateEntry(testfilename, CompressionLevel.NoCompression);
using (var writer = new StreamWriter(newEntry.Open(), utf8WithoutBom))
{
writer.Write(testFileContent);
writer.Flush();
}
byte[] fileContent = testStream.ToArray();
// zip file header stores values as little-endian
byte compressionMethod = fileContent[8];
Assert.Equal(0, compressionMethod); // stored => 0, deflate => 8
uint compressedSize = BitConverter.ToUInt32(fileContent, 18);
uint uncompressedSize = BitConverter.ToUInt32(fileContent, 22);
Assert.Equal(uncompressedSize, compressedSize);
byte filenamelength = fileContent[26];
Assert.Equal(testfilename.Length, filenamelength);
string readFileName = ReadStringFromSpan(fileContent.AsSpan(30, filenamelength));
Assert.Equal(testfilename, readFileName);
string readFileContent = ReadStringFromSpan(fileContent.AsSpan(30 + filenamelength, testFileContent.Length));
Assert.Equal(testFileContent, readFileContent);
}
}
}
public void UpdateUncompressedArchive()
{
var utf8WithoutBom = new Text.UTF8Encoding(encoderShouldEmitUTF8Identifier: false);
byte[] fileContent;
using (var memStream = new MemoryStream())
{
using (var zip = new ZipArchive(memStream, ZipArchiveMode.Create))
{
ZipArchiveEntry entry = zip.CreateEntry("testing", CompressionLevel.NoCompression);
using (var writer = new StreamWriter(entry.Open(), utf8WithoutBom))
{
writer.Write("hello");
writer.Flush();
}
}
fileContent = memStream.ToArray();
}
byte compressionMethod = fileContent[8];
Assert.Equal(0, compressionMethod); // stored => 0, deflate => 8
using (var memStream = new MemoryStream())
{
memStream.Write(fileContent);
memStream.Position = 0;
using (var archive = new ZipArchive(memStream, ZipArchiveMode.Update))
{
ZipArchiveEntry entry = archive.GetEntry("testing");
using (var writer = new StreamWriter(entry.Open(), utf8WithoutBom))
{
writer.Write("new");
writer.Flush();
}
}
byte[] modifiedTestContent = memStream.ToArray();
compressionMethod = modifiedTestContent[8];
Assert.Equal(0, compressionMethod); // stored => 0, deflate => 8
}
}