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This article will explain in detail how to get each byte of integers in C++. The editor thinks it is very practical, so I share it for you as a reference. I hope you can get something after reading this article.

Topic: get each byte of 0x12345678.

Method 1: structure & Joint # include

Typedef unsigned int uint32_t

Typedef unsigned char uint8_t

Union bit32_data

{

Uint32_t data

Struct

{

Uint8_t byte0

Uint8_t byte1

Uint8_t byte2

Uint8_t byte3

} byte

}

Int main (void)

{

Union bit32_data num

Num.data = 0x12345678

Printf ("byte0 = 0x%x\ n", num.byte.byte0)

Printf ("byte1 = 0x%x\ n", num.byte.byte1)

Printf ("byte2 = 0x%x\ n", num.byte.byte2)

Printf ("byte3 = 0x%x\ n", num.byte.byte3)

Return 0

}

Running result:

The disadvantage of this method is that it will be affected by the size of the end. It can only be used slightly if the size of the end is clear. The above is the result of running in small-end mode.

The structure-federation method is not only useful in obtaining each byte of data, but also useful in data protocol, data bit splitting, etc., and then share it in more detail.

Method 2: shift operation # include

# define GET_LOW_BYTE0 (x) ((x > > 0) & 0x000000ff) / * get the 0th byte * /

# define GET_LOW_BYTE1 (x) ((x > 8) & 0x000000ff) / * get the first byte * /

# define GET_LOW_BYTE2 (x) ((x > > 16) & 0x000000ff) / * get the second byte * /

# define GET_LOW_BYTE3 (x) ((x > 24) & 0x000000ff) / * get the third byte * /

Int main (void)

{

Unsigned int a = 0x12345678

Printf ("byte0 = 0x%x\ n", GET_LOW_BYTE0 (a))

Printf ("byte1 = 0x%x\ n", GET_LOW_BYTE1 (a))

Printf ("byte2 = 0x%x\ n", GET_LOW_BYTE2 (a))

Printf ("byte3 = 0x%x\ n", GET_LOW_BYTE3 (a))

Return 0

}

Running result:

This is also the most common and effective way to get each byte of data. This similar bit operation is widely used in embedded systems, such as representing pixel color values in LCD operations, FLASH operations, and so on.

This is the end of the article on "how to get integer bytes in C++". I hope the above content can be of some help to you, so that you can learn more knowledge. If you think the article is good, please share it for more people to see.

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