在库中调用scanf函数

Question

我从.h文件中调用scanf函数时遇到了麻烦。

mylib.h

intnums() //Entering 2 numbers
    {
        textcolor(WHITE);
        printf("\nIntroduza dois números para realizar a operação selecionada.\n");
        scanf("%i%i",&a,&b);
    }

sumsub.h

sum(int a, int b) //Operation using previous introduction
{
    textcolor(WHITE);
    printf("\nA soma é: %i\n",a+b);
}

main.c中

case 1:
    linha();
    intnums();
    sum(int b, int c);
    delay4sec();
    clear();
    break; 


//intnums calls for the function of entering the numbers and sum uses the entered numbers in intnums to calculate.

我是编码的新手，我仍然不太了解它，因此我想请求帮助来解决这个问题。提前谢谢。

Answer 1

您必须使用extern关键字在文件之间共享变量

mylib.h

#include<stdio.h>
extern a,b;
intnums() //Entering 2 numbers
    {
        textcolor(WHITE);
        printf("\nIntroduza dois números para realizar a operação selecionada.\n");
        scanf("%i%i",&a,&b);
    }

sumsub.h

sum(int a, int b) //Operation using previous introduction
{
    textcolor(WHITE);
    printf("\nA soma é: %i\n",a+b);
}

main.c中

case 1:
    linha();
    intnums();
    sum(a,b);// you don,t have to use data type to pass the variable a&b are extern which are read by mylib.h
    delay4sec();
    clear();
    break;