Hi,
I faced an issue w/ the BinaryFormatter in PS, which took me a couple of hours to understand **why** -- as I never saw it happen in C#!
Not really sure if this is the expected behavior... so trying to figure out if this is a feature... or a bug!
Here it is...
For this example, I used up a text file, called aaa, with 10K+ bytes. And yes, in this example, size does matter!
Also, the file serialization is not the goal... is just an easy way to have a considerable array of data of different data types.
PS C:\temp> dir aaa
Directory: C:\temp
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 2017-10-20 16:40 13542 aaa
Loading and serializing the file, looks trivial:
PS C:\temp> $x=gc .\aaa
PS C:\temp> $x.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
PS C:\temp> $x[0].GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True String System.Object
PS C:\temp> $x.Length
33
PS C:\temp> $ms=New-Object System.IO.MemoryStream; try{ date; (New-Object System.Runtime.Serialization.Formatters.Binary.BinaryFormatter).Serialize( $ms, $x); date; $ms.Length }Finally{ $ms.Close() }
Monday, Nov 20, 2017 15:01:45
Monday, Nov 20, 2017 15:01:45
93333
So, the serialization of the object[] happens in a glitch, no issues so far.
However, when I import the file as a byte[]:
PS C:\temp> $x=gc .\aaa -Encoding Byte
PS C:\temp> $x.Length
13542
PS C:\temp> $x.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
PS C:\temp> $ms=New-Object System.IO.MemoryStream; try{ date; (New-Object System.Runtime.Serialization.Formatters.Binary.BinaryFormatter).Serialize( $ms, $x); date; $ms.Length }Finally{ $ms.Close() }
Monday, Nov 20, 2017 15:03:01
Monday, Nov 20, 2017 15:06:57
35557612
Not only the serialized image is 381 times bigger than the text one, as it takes almost 4 mins to serialize it!!
If however, I force the cast to byte[]
PS C:\temp> $x=[byte[]]$x
PS C:\temp> $x.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Byte[] System.Array
PS C:\temp> $ms=New-Object System.IO.MemoryStream; try{ date; (New-Object System.Runtime.Serialization.Formatters.Binary.BinaryFormatter).Serialize( $ms, $x); date; $ms.Length }Finally{ $ms.Close() }
Monday, Nov 20, 2017 15:07:58
Monday, Nov 20, 2017 15:07:58
13570
It gives a more acceptable size and is done in a glitch!
I thought it may be due to boxing; as in the first byte[] load, $x was object[], it is probably boxing each byte in an object... so, I decided to box, not a byte[] but a int[], expecting similar results. However...
PS C:\temp> $x=[object[]][int[]]$x
PS C:\temp> $x.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
PS C:\temp> $x[0].GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Int32 System.ValueType
PS C:\temp> $ms=New-Object System.IO.MemoryStream; try{ date; (New-Object System.Runtime.Serialization.Formatters.Binary.BinaryFormatter).Serialize( $ms, $x); date; $ms.Length }Finally{ $ms.Close() }
Monday, Nov 20, 2017 15:08:38
Monday, Nov 20, 2017 15:08:38
81279
It currently looks well!
I made many more experiments and looks like that when is a byte[], the system runs wild and the serialization takes forever.
I definitely need to force the cast to byte[] to have a normal behavior... However, any other type (any array of any value type, not byte, or class) works as expected.
Am I missing something ??
Best regards,
José
