Issue with trying to use GZipStream in C# to decompress a large gz file

Question

I'm trying to use GZipStream in C# to decompress a large gz file (compressed 2.5 GB -> decompressed 30 GB). Using the following code and the output file is always 50KB. I tried the same code on a much smaller gz file ~500MB and it worked fine. Wondering if there is any limitation to the GZipStream class. Below is my code, I got it from https://learn.microsoft.com/en-us/dotnet/api/system.io.compression.gzipstream?view=net-7.0

    private static void DecompressFile()
    {
        using (FileStream compressedFileStream = File.Open(gzipFilePath, FileMode.Open))         
		using (FileStream outputFileStream = File.Create(destinationFilePath))         
		using (var decompressor = new GZipStream(compressedFileStream, CompressionMode.Decompress))         		   	
		{             
			decompressor.CopyTo(outputFileStream);         
		}
    }

    
    ```

Answer 1

Hi @Zed Yang ,

Please put decompressor. CopyTo(outputFileStream); in curly brackets after the Using statement to prevent the stream from being closed prematurely.

       private static void DecompressFile()
        {
            using (FileStream compressedFileStream = File.Open(CompressedFileName, FileMode.Open))
            using (FileStream outputFileStream = File.Create(DecompressedFileName))
            using (GZipStream decompressor = new GZipStream(compressedFileStream, CompressionMode.Decompress))
            {
                decompressor.CopyTo(outputFileStream);
            }
        }

Also try to use the TryCatch statement to catch possible exceptions.

Best Regards.

Jiachen Li

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