*

[Pointer Access Operators]

描述

Dereferencing is one of the features specifically for use with pointers. The asterisk operator * is used for this purpose. If p is a pointer, then *p represents the value contained in the address pointed by p.

Example Code

int *p;       // declare a pointer to an int data type
int i = 5;
int result = 0;
p = &i;       // now 'p' contains the address of 'i'
result = *p;  // 'result' gets the value at the address pointed by 'p'
              // i.e., it gets the value of 'i' which is 5

Tip

Pointers are one of the complicated subjects for beginners in learning C, and it is possible to write the vast majority of Arduino sketches without ever encountering pointers. However for manipulating certain data structures, the use of pointers can simplify the code, and knowledge of manipulating pointers is handy to have in one’s toolkit.

參考


語法參考主頁面

86Duino 參考的文本是根據 Creative Commons Attribution-ShareAlike 3.0 License,部分文本是從 the Arduino reference 修改的。 參考中的代碼示例已發佈到公共領域。

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