填充作为成员变量的int数组

Question

我正在使用C++为游戏创建一个平铺地图.我的问题是,我想在Map构造函数中填充一个多维的int数组,但它不能正常工作.这是我在"Map.h"中的代码(不相关的代码已被删除).

class Map {

private:    
int mapArray[15][20];

};

我的代码来自Map.cpp

Map::Map()
{

    mapArray = {
        { 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 },
        { 20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39 },
        { 40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59 },
        { 60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79 },
        { 80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99 },
        { 100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119 },
        { 120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139 },
        { 140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159 },
        { 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179 },
        { 180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199 },
        { 200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219 },
        { 220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239 },
        { 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,256,257,258,259 },
        { 260,261,262,263,264,265,266,267,268,269,270,271,272,273,274,275,276,277,278,279 },
        { 280,281,282,283,284,285,286,287,288,289,290,291,292,293,294,295,296,297,298,299 }
    };


}

PS.使用int mapArray [15] [20]在一个成员函数中本地创建mapArray并填充它然后工作正常,我似乎无法使用成员变量在构造函数中填充它.

PPS.用C++非常生疏,请温柔.

我究竟做错了什么？

谢谢,詹姆斯.

Answer 1

您不能在类构造函数中使用这样的数组初始值设定项.只能使用初始化列表初始化成员.最好的办法是从文件中加载这些数据,或者将数组声明为静态数据.

class Map
{
private:
static int mapArray[15][20];
/* ... */
};

然后在源文件(.cpp)中定义静态数组的存储,也称为转换单元:

int Map::mapArray[15][20] = { ... };

Answer 2

你应该可以做这样的事情:

class Map
{
  int mapArray[15][20];

  public:
  Map() : mapArray( (int[15][20]) {
    { 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 },
    { 20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39 },
    { 40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59 },
    { 60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79 },
    { 80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99 },
    { 100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119 },
    { 120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139 },
    { 140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159 },
    { 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179 },
    { 180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199 },
    { 200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219 },
    { 220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239 },
    { 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,256,257,258,259 },
    { 260,261,262,263,264,265,266,267,268,269,270,271,272,273,274,275,276,277,278,279 },
    { 280,281,282,283,284,285,286,287,288,289,290,291,292,293,294,295,296,297,298,299 }
  } )
  {
  }
};

请注意,此初始化样式是C99的一部分,可能不包含在编译器中,也可能不适用于C++.适用于GCC 4.

另请注意,我没有编译此代码.我根据你的其他一些代码调整了你的情况.