如何将数组作为参数传递给vararg函数?

时间:2023-02-13 15:06:51

I have some code that looks like this:

我有一些看起来像这样的代码:

uint8_t activities[8];
uint8_t numActivities = 0;
...
activities[numActivities++] = someValue;
...
activities[numActivities++] = someOtherValue;
...
switch (numActivities)
{
   0 : break;
   1 : LogEvent(1, activities[0]);  break;
   2 : LogEvent(1, activities[0], activities[1]);  break;
   3 : LogEvent(1, activities[0], activities[1], activities[2]);  break;
   // and so on
}

where LogEvent() is a varargs function.

其中LogEvent()是一个varargs函数。

Is there a more elgant way to do this?

有没有更优雅的方式来做到这一点?


[Update] Aplogies to @0x69 et al. I omitted to say that there are many cases where LogEvent() could not take an array as a parameter. Sorry.

[更新] Aplogies @ @ 0x69等。我没有说,有很多情况下LogEvent()无法将数组作为参数。抱歉。

2 个解决方案

#1


4  

There's no standard way to construct or manipulate va_args arguments, or even pass them to another function (Standard way to manipulate variadic arguments?, C Programming: Forward variable argument list). You'd be better off seeing if you can access the internal routines of LogEvent.

没有标准的方法来构造或操纵va_args参数,甚至将它们传递给另一个函数(操作可变参数的标准方法?,C编程:转发变量参数列表)。你最好看看你是否可以访问LogEvent的内部例程。

#2


2  

pass a pointer to the array of ints and a number of ints instead

传递一个指向int数组和一些int的指针

#include <stdio.h>

void logevent(int n, int num, int *l) {
    int i;
    for (i=0; i<num; i++) {
        printf("%d %d\n",n,*(l++));
    }
    }

int main() {

    int activities[8];
    activities[0]=2;
    activities[1]=3;
    activities[2]=4;
    int num=3;
    int n=1;
    logevent(n,num, activities);
    printf("=========\n");
    n=2;
    activities[3]=5;
    num=4;
    logevent(n,num, activities);

}

#1


4  

There's no standard way to construct or manipulate va_args arguments, or even pass them to another function (Standard way to manipulate variadic arguments?, C Programming: Forward variable argument list). You'd be better off seeing if you can access the internal routines of LogEvent.

没有标准的方法来构造或操纵va_args参数,甚至将它们传递给另一个函数(操作可变参数的标准方法?,C编程:转发变量参数列表)。你最好看看你是否可以访问LogEvent的内部例程。

#2


2  

pass a pointer to the array of ints and a number of ints instead

传递一个指向int数组和一些int的指针

#include <stdio.h>

void logevent(int n, int num, int *l) {
    int i;
    for (i=0; i<num; i++) {
        printf("%d %d\n",n,*(l++));
    }
    }

int main() {

    int activities[8];
    activities[0]=2;
    activities[1]=3;
    activities[2]=4;
    int num=3;
    int n=1;
    logevent(n,num, activities);
    printf("=========\n");
    n=2;
    activities[3]=5;
    num=4;
    logevent(n,num, activities);

}