如何在运行时为struct数组赋值？

I declared an array of struct and initialized it at compile time.

我声明了一个struct数组并在编译时初始化它。

Now, for unit testing purposes, I would like to initialize it from a function which I can call from main() and from my unit tests.

现在,出于单元测试的目的,我想从一个函数初始化它,我可以从main()和单元测试中调用它。

For some reason, probably involving a 16 hour coding marathons & exhaustion, I can't figure it out.

出于某种原因,可能涉及16小时的编码马拉松和疲惫,我无法弄明白。

3 个解决方案

#1

So assuming you have

所以假设你有

struct foo {
   int a;
   int b;
};

struct foo foo_array[5] = {
 { 0, 0 }, { 1, 1 }, { 2, 2 }
};


int main() { 
     memcpy(foo_array, some_stuff, sizeof(foo_array)); // should work
    ...

OR you could:

或者你可以:

int main() {
    int i;
    for ( i = 0; i < sizeof(foo_array)/sizeof(struct foo); i++ ) {
           init(&foo_array[i]);
    }
}

but without looking at your code it's hard to say what's causing the trouble... i am SURE it's probably something very trivial you are overlooking because you are tired and have been at it for 16 hours.

但是没有看你的代码,很难说是什么导致了麻烦......我确定你可能会忽略一些非常微不足道的东西,因为你已经累了16个小时。

#2

typedef struct {
  int ia;
  char * pc;
} St_t;

void stInit(St_t * pst) {
  if (!pst)
    return;

  pst->ia = 1;
  pst->pc = strdup("foo");

  /* Assuming this function 'knows' the array has two elements, 
     we simply increment 'pst' to reference the next element. */
  ++ pst;

  pst->ia = 2;
  pst->pc = strdup("bar");

}

void foo(void) {
  /* Declare 'st' and set it to zero(s)/NULL(s). */
  St_t st[2] = {{0}, {0}};

  /* Initialise 'st' during run-time from a function. */
  stInit(st);

  ...
}

#3

see this one:

看到这一个:

struct Student
{
    int rollNo;
    float cgpa;
};

int main()
{
    const int totalStudents=10;

    Student studentsArray[totalStudents];

    for(int currentIndex=0; currentIndex< totalStudents; currentIndex++)
    {
          printf("Enter Roll No for student # %d\n" , currentIndex+1);
          scanf("%d\n", &studentsArray[currentIndex].rollNo);

          printf("Enter CGPA for student # %d\n", currentIndex+1);
          scanf("%d\n", &studentsArray[currentIndex].cgpa);
     }
}

#1