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在函数c中返回结构

[英]Returning structs in function c

I'm trying to return a struct from a function. 我正在尝试从函数返回struct It looks like this.. 看起来像这样..

struct read(struct returnera returnDuo, struct vara varuArray[]) { 
     char varunr[LISTNUMBER], varunamn[LISTNUMBER];
     FILE *varuLista;
     varuLista = fopen(returnDuo.filnamn, "r");
     if(varuLista!=NULL) {
         while(fscanf(varuLista,"%s\t%s\t%d\n",varunr, varunamn, 
                      &varuArray[returnDuo.antalVaror].lagerSaldo) == 3){ 
            strncpy(varuArray[returnDuo.antalVaror].varuNr,varunr,5);
            strncpy(varuArray[returnDuo.antalVaror].varuNamn,varunamn,30);
            returnDuo.antalVaror++;
        } 
        printf("Filen är laddad..\n"); 
        kommaVidare();
     }
     else {
        printf("Filen hittades inte, skapar en tom fil"); kommaVidare();
     }
     fclose(varuLista);
     return returnDuo;
 }

I'm trying to return the content in the returnDuo struct but I get the error message: "Expected identifier or '('". If I use void function its working as expected without returning anything but I cant figure out how to return this struct . 我试图返回returnDuo结构中的内容,但收到错误消息:“ Expected identifier or'('”。如果我使用void函数,按预期工作,但不返回任何内容,但我无法弄清楚如何返回此struct

This is how I setup the structs. 这就是我设置结构的方式。

struct vara {
    char varuNr[5];
    char varuNamn[50];
    int lagerSaldo;
};

struct returnera {
    int antalVaror;
    char filnamn[LISTNUMBER];
};

And how I setup them up in main. 以及我如何在主目录中设置它们。

struct vara varuArray[SIZE];

struct returnera returnDuo = {0,"0"};

I gladly take any tips on how to get this to work... 我很高兴就如何使它起作用的任何技巧...

it should be 它应该是

struct returnera read(struct returnera returnDuo, struct vara varuArray[])

not

struct read(struct returnera returnDuo, struct vara varuArray[])

This is a good case for using a typedef. 这是使用typedef的好例子。 Declaring a typedef to the struct provides a compact single-word name for the struct type. 对结构声明typedef可以为结构类型提供紧凑的单字名称。 Example: 例:

#include "stdio.h"

typedef struct Item_Struct {
    int val;
} Item;

Item Update( Item item, int val )
{
    item.val = val;
    return item;
}

int main( int argc, char** argv )
{
    Item item;
    printf( "Item -> %i\n", Update(item,4).val ); // Prints "Item -> 4"
    return 0;
}

Note that in C++ (as opposed to C) you can simply use the name of the struct by itself: 请注意,在C ++中(相对于C),您可以简单地单独使用struct的名称:

returnera read(returnera returnDuo, vara varuArray[])

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