c++ - 声明和初始化指针到指针字符数组

Question

关于指向指针的指针，我想知道它是否适合以下内容:

    char** _charPp = new char*[10];

     for (int i = 0; i < 10; i++)
    ´   _charPp[i] = new char[100];

也就是说 - 如果我想要一个指向 10 个字符数组的指针。

问题 - 现在可以了吗，还是我必须对每个字符数组进行某种初始化？那么 - 我该怎么做？

稍后我会在程序中用某些字符填充这些数组，但我怀疑数组应该用之前的值初始化，例如“0”

Answer 1

是的，看起来很合适，

int arraySizeX = 100;
int arraySizeY = 100;
char** array2d = new char*[arraySizeX] // you've just allocated memory that
                                       // holds 100 * 4 (average) bytes
for(int i = 0; i < arraySizeX; ++i)
{
    array2d[i] = new char[arraySizeY] // you've just allocated a chunk that 
                                       //holds 100 char values. It is 100 * 1 (average) bytes
    memset(array2d[i], 0, arraySizeY) // to make every element NULL
}

I will later on in the program fill these arrays with certain chars but i suspect that the arrays should be initialized with values before such as "0"

不，C++ 中没有“默认值”。您需要将 0 分配给指针以使其为空，或使用 memset() 对数组执行此操作。