LAS 2.0 data types and corresponding data types in .NET

The LAS2.0's specification defines the data types it supports in table 3.1 on page 4.

The following table shows the corresponding .NET data types as well as the C# built in data type.

LAS 2.0 Moniker	Data Type	Size (in bytes)	.NET Data Type	C# Type	Range
BOOL	Logical	1	Boolean	bool	true or false
B1	Byte	1	SByte	sbyte	-128 to 127
UI1	Unsigned Byte	1	Byte	byte	0 to 255
I2	Signed Short Integer	2	Int16	short	-32768 to 32767
UI2	Unsigned Short Integer	2	UInt16	ushort	0 to 65535
I4	Signed Long Integer	4	Int32	int	2,147,483,648 to 2,147,483,647
UI4	Unsigned Long Integer	4	UInt32	uint	0 to 4,294,967,295
I8	Signed 8 byte integer	8	Int64	long	-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
UI8	Unsigned 8 byte integer	8	UInt64	ulong	0 to 18,446,744,073,709,551,615
R4	Real Float	4	Single	float
R8	Real Double	8	Double	double
R10	Real Extended precision Double	10	??	??
STR	STR zero (null – binary 0000 0000) terminated variable length string	VAR	Byte[]	byte[]	Even though the data is stored as an array of bytes, one can use the string data type and use convertors to convert the string to the byte values. Also remember the values are not the .NET Char type which is 2 bytes in size
BFx	bit field	x, where x = 1,2,4,8	Byte, UInt16, UInt32, UInt64	byte, ushort, uint, ulong	data types are used as bit fields
[n]	Array	VAR	Array	Array of any of the types defined above	for example UI[4] is uint[4]

Notes:

• The BitConvertor class as well as the BinaryReader class can be used to convert bytes to their corresponding .NET data types.
• To convert a byte array to string one can do the following:

public static byte[] StrToByteArray(string str)
{  
    System.Text.ASCIIEncoding encoding=new System.Text.ASCIIEncoding();  
    return encoding.GetBytes(str);
}

• And to do the reverse

byte [] dBytes = ...
string str;
System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
str = enc.GetString(dBytes);

• The BitArray class (System.Collections namespace) can be used as a helper class to work with the BFx data type. It can handle arbitrary length bit fields and provides methods that allow you to perform bit arithmetic.
• An important thing to remember is that bool in .NET is actual 4 bytes long (which corresponds to a WIN BOOL). So if you need to marshal your structure to native code or need to convert the data to bytes - you will need to use the Marshal As attribute to do it as a byte (UI1)

More information:
C# Data Type:
http://msdn2.microsoft.com/en-us/library/1dhd7f2x(VS.71).aspx 
LAS 2.0 Specification:
http://www.asprs.org/society/divisions/ppd/standards/incitsl1_las_format_v20.pdf 
LAS Documents:
http://www.asprs.org/society/divisions/ppd/standards/lidar_exchange_format.htm