typedef结构数组。他们是如何工作的？ [英] typedef struct arrays. How do they work?

问题描述

我已经注意到它们与普通数组的工作方式不同，只是简单地编写

i have noted they don't really work the same as normal arrays that simply write

int x[20]={0};

这将使一个阵列与20 0相继。

但是如果我尝试用struct做同样的事情它会快速向南。

this will make a array with 20 0's after one another.
but if i try to do the same thing with struct's it goes south fast.

typedef struct FancyName {
     int x[20];
};

int _tmain(int argc, _tchar* argv[])
{
     FancyName Fancy;
     Fancy.x={0};
}

以下错误将无法从'int'转换为'int [100]'。

和nomatter我怎么写编译器都不会执行它。

the following errors would be "cannot convert from 'int' to 'int[100]'".
and nomatter how i write the compiler will not execute it.

Fancy.x[]={0};
Fancy.x[0]={0};
Fancy.x={0};

所以我的问题是如何轻松地将结构数组的所有值更改为一个值？

so my question becomes how do i easely change all the values of a struct array to one value?

推荐答案

最简单的方法是

the easiest way is

typedef struct FancyName {
     int x[20];
};

FancyName Fancy;

memset( Fancy, 0, sizeof(Fancy) );

另一种方法是将struct和memcopy初始化为另一个

Another way is to initialize a struct and memcopy to another

FancyName source;
source.x[0] = 3; //for illustration
FancyName Fancy;

memcpy( Fancy, source, sizeof(Fancy) );

最后一种方法是在结构数组中进行愚蠢的循环。



你的结构是有意义的，因为它是一个数组。这里的结构更有意义：

The last way is stupid looping in arrays of struxts.

your struct is lagging of sense, because it is an array. structs making more sense like here:

typedef struct ColorPoint{
 int x; //coordinate
 int y; //coordinate
 int z; //coordinate
 int color; //color value
 float alpha;//alpha value

ColorPoint colorPoint;
colorPoint.x = 1;
colorPoint.y = 2;
colorPoint.z = 3;
colorPoint.color = 0xff;//red
colorPoint.alpha = 0.5; //half transparent

Quote：

typedef struct FancyName {

int x [20];

};

typedef struct FancyName {
int x[20];
};

使用 C ++ 编程语言，你不需要 typedef 。







你可以通过这种方式执行inizialization

Using the C++ programming language, you don't need the typedef.



You might perform the inizialization to zero this way

FancyName fc = {{0}};

或使用现代 C ++ 编译器

or, using a modern C++ compiler

FancyName fc{};

这将默认初始化结构的所有成员（参见 C ++ 11 - 新的ISO C ++标准：统一初始化 [ ^ ]）。

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