Update Table.cs

[KanouAo]

Fix memory alignment issue: calculate correct byte length (element count × element size)
Just add a line : var byteLen = len * System.Runtime.InteropServices.Marshal.SizeOf();
#8759

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[bjornharrtell]

@aardappel this looks sensible to me but I'm not entirely sure, can you take a look?

[aardappel]

Hmm, this seems a bug indeed, wonder why no-one has ever run into it?

Why not use https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/operators/sizeof ?
The call you're making generally amounts to the same thing, but does type introspection for more complex types of T, would not trust it to be as cheap as the operator.

[aardappel]

Also on that link:

The value returned by sizeof can differ from the result of [Marshal.SizeOf(Object)](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.marshal.sizeof#system-runtime-interopservices-marshal-sizeof(system-object)), which returns the size of the type in unmanaged memory.

Apparently unmanaged bool can become 4 bytes etc, not corresponding to FlatBuffers types anymore.