VB6進行GZIP解壓&C#進行GZIP壓縮和解壓

VB進行GZIP解壓的,DLL是系統的,若是沒有 [點擊下載]

 1 Option Explicit
 2 'GZIP API
 3 '--------------------------------------------------
 4 Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
 5 Private Declare Function InitDecompression Lib "gzip.dll" () As Long
 6 Private Declare Function CreateDecompression Lib "gzip.dll" (ByRef context As Long, ByVal Flags As Long) As Long
 7 Private Declare Function DestroyDecompression Lib "gzip.dll" (ByRef context As Long) As Long
 8 Private Declare Function Decompress Lib "gzip.dll" (ByVal context As Long, inBytes As Any, ByVal input_size As Long, outBytes As Any, ByVal output_size As Long, ByRef input_used As Long, ByRef output_used As Long) As Long
 9 '=============================================================
10 '2012-10-5
11 'gzip解壓,返回值表示是否成功,若是成功,解壓結果經過址參回傳
12 '=============================================================
13 Public Function UnGzip(ByRef arrBit() As Byte) As Boolean
14     On Error GoTo errline
15     Dim SourceSize  As Long
16     Dim buffer()    As Byte
17     Dim lReturn    As Long
18     Dim outUsed    As Long
19     Dim inUsed      As Long
20     Dim chandle As Long
21     If arrBit(0) <> &H1F Or arrBit(1) <> &H8B Or arrBit(2) <> &H8 Then
22         Exit Function '不是GZIP數據的字節流
23     End If
24     '獲取原始長度
25     'GZIP格式的最後4個字節表示的是原始長度
26     '與最後4個字節相鄰的4字節是CRC32位校驗,用於比對是否和原數據匹配
27     lReturn = UBound(arrBit) - 3
28     CopyMemory SourceSize, arrBit(lReturn), 4
29     '重點在這裏,網上有些代碼計算解壓存放空間用了一些奇怪的公式
30     '如:L = 壓縮大小 * (1 + 0.01) + 12
31     '不知道怎麼獲得的,用這種方式偶爾會報錯...
32     '這裏的判斷是由於:(維基)一個壓縮數據集包含一系列的block（塊），只要未壓縮數據大小不超過65535字節，塊的大小是任意的。
33     'GZIP基本頭是10字節
34     If SourceSize > 65535 Or SourceSize < 10 Then
35         '測試用,申請100KB空間嘗試一下
36         'SourceSize = 102400
37         Exit Function
38     Else
39         SourceSize = SourceSize + 1
40     End If
41     ReDim buffer(SourceSize) As Byte
42     '建立解壓縮進程
43     InitDecompression
44     CreateDecompression chandle, 1  '建立
45     '解壓縮數據
46     Decompress ByVal chandle, arrBit(0), UBound(arrBit) + 1, buffer(0), SourceSize + 1, inUsed, outUsed
47     If outUsed <> 0 Then
48         DestroyDecompression chandle
49         ReDim arrBit(outUsed - 1)
50         CopyMemory arrBit(0), buffer(0), outUsed
51         UnGzip = True
52     End If
53     Exit Function
54 errline:
55 End Function

C#進行GZIP壓縮和解壓，參考[MSDN]

 1 public static byte[] GZipCompress(byte[] buffer)
 2 {
 3     using (MemoryStream ms = new MemoryStream())
 4     {
 5         GZipStream Compress = new GZipStream(ms, CompressionMode.Compress);
 6         Compress.Write(buffer, 0, buffer.Length);
 7         Compress.Close();
 8         return ms.ToArray();
 9     }
10 }
11 public static byte[] GZipDecompress(byte[] buffer)
12 {
13     using (MemoryStream tempMs = new MemoryStream())
14     {
15         using (MemoryStream ms = new MemoryStream(buffer))
16         {
17             GZipStream Decompress = new GZipStream(ms, CompressionMode.Decompress);
18             Decompress.CopyTo(tempMs);
19             Decompress.Close();
20             return tempMs.ToArray();
21         }
22     }
23 }