C语言：字符指针和字符数组的区别

对于这行代码： char amessage[] = "now is the time";

编译器将评估对amessage的使用，作为指向包含字符“now is the time”的数组开头的指针。编译器为“now is the time”分配内存，并用字符串“now is the time”初始化它。您知道消息存储在哪里，因为amessage始终指向该消息的开头。amessage可能不会被赋予新值-它不是变量，而是字符串“now is the time”的名称。

这行代码： char *pmessage = "now is the time";

声明一个变量pmessage，它的初始化（给定初始值）为字符串“now is the time”的起始地址。与amessage不同，pmessage可以被赋予新值。在这种情况下，与前面的情况一样，编译器还将“now is the time”存储在内存中的其他位置。 例如，这将导致pmessage指向以“is the time”开头的“i”。 pmessage = pmessage + 4;

这是我为自己总结的数组和指针之间主要区别：

//ATTENTION:
    //Pointer depth 1
     int    marr[]  =  {1,13,25,37,45,56};      // array is implemented as a Pointer TO THE FIRST ARRAY ELEMENT
     int*   pmarr   =  marr;                    // don't use & for assignment, because same pointer depth. Assigning Pointer = Pointer makes them equal. So pmarr points to the first ArrayElement.

     int*   point   = (marr + 1);               // ATTENTION: moves the array-pointer in memory, but by sizeof(TYPE) and not by 1 byte. The steps are equal to the type of the array-elements (here sizeof(int))

    //Pointer depth 2
     int**  ppmarr  = &pmarr;                   // use & because going one level deeper. So use the address of the pointer.

//TYPES
    //array and pointer are different, which can be seen by checking their types
    std::cout << "type of  marr is: "       << typeid(marr).name()          << std::endl;   // int*         so marr  gives a pointer to the first array element
    std::cout << "type of &marr is: "       << typeid(&marr).name()         << std::endl;   // int (*)[6]   so &marr gives a pointer to the whole array

    std::cout << "type of  pmarr is: "      << typeid(pmarr).name()         << std::endl;   // int*         so pmarr  gives a pointer to the first array element
    std::cout << "type of &pmarr is: "      << typeid(&pmarr).name()        << std::endl;   // int**        so &pmarr gives a pointer to to pointer to the first array elelemt. Because & gets us one level deeper.

数组是一个常量指针。你不能更新它的值并使其指向其他地方。 而对于指针，你可以这样做。