C# is not the same as C or C++!!!!!  Simple byte operations for example do not result in a byte result, they often result in an Int32 result

An example binary operation

This will generat the error “Cannot implicitly convert type ‘int’ to ‘byte’. An explicit conversion exists (are you missing a cast)”:

	TxData[ByteIndex++] = (byte)TagIdCharacter[0] | 0x80;

Its because the result of the IOR operation does not result in a byte, so you need to use parenthesis:

	TxData[ByteIndex++] = (byte)(TagIdCharacter[0] | 0x80);

Gotchas!

Convert.ToInt16( … ) does not work error free! If you try and convert 0x0000FFFF) for instance it will generate an error! However using (Int16) won’t. Here’s an example

This generates a ‘Value to big or small’ error:

	Byte[] RxData = new Byte[10];
	RxData[0] = 0xff;
	RxData[1] = 0xff;
	Temperature = Convert.ToInt16((Convert.ToInt16(RxData[0]) << 8) | RxData[1]);

This works fine and produces the correct -1 result:

	Byte[] RxData = new Byte[10];
	RxData[0] = 0xff;
	RxData[1] = 0xff;
	Temperature = (Int16)((Convert.ToInt16(RxData[0]) << 8) | RxData[1]);

Examples

Merge 2 bytes values into a Int16 variable

Remember the result of an OR operation is Int32, and you can’t convert 0x0000FFFF to Int16 using ConvertTo, but this works fine:

	Byte[] RxData = new Byte[10];
	RxData[0] = 0xff;
	RxData[1] = 0xff;
	Temperature = (Int16)((Convert.ToInt16(RxData[0]) << 8) | RxData[1]);
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