How to set endianness when converting to or from hexadecimal strings

Question

To convert an integer to a hexadecimal formatted string, I use ToString ("X4") as follows:

int target = 250;    
string hexString = target.ToString("X4");

To get an integer value from a hexadecimal formatted string, I use the Parse method:

int answer = int.Parse(data, System.Globalization.NumberStyles.HexNumber);

However, the machine I am exchanging data with puts the bytes in the reverse order.

To save sample data, if I want to send the value 250, I need the string "FA00" (not 00FA, which is hexString). Similarly, if I get "FA00", I need to convert this value to 250 64000.

How to establish the finiteness of these two conversion methods?

Answer 1

. , , , I.e.

int otherEndian = (value << 16) | (((uint)value) >> 16);

Answer 2

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:

int target = 250; // 0x00FA

// swap the bytes of target
target = ((target << 8) | (target >> 8)) & 0xFFFF;

// target now is 0xFA00
string hexString = target.ToString("X4");

, , 16- , 32- int. 16- ( 16 , <<).

32- :

int target = 250; // 0x00FA

// swap the bytes of target
target = (int)((int)((target << 24) & 0xff000000) |
    ((target << 8) & 0xff0000) |
    ((target >> 8) & 0xff00) |
    ((target >> 24) & 0xff));

// target now is 0xFA000000
string hexString = target.ToString("X8");

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, , , NetworkToHostOrder(). , , big-endian, HostToNetworkOrder().

: Int16, Int32 Int64 ( #, short, int long ). , , . :

int target = 250; // 0x00FA

// swap the bytes of target
target = IPAddress.HostToNetworkOrder((short)target) & 0xFFFF;

// target now is 0xFA00
string hexString = target.ToString("X4");

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