在 C 中，我如何评估一个函数中的局部变量，在不同的函数中？

Posted 2023-02-23

【中文标题】在 C 中，我如何评估一个函数中的局部变量，在不同的函数中？

【英文标题】：In C, How can I evaluate a local variable thats in one function, in a different function?

【发布时间】：2014-01-24 15:53:54

【问题描述】：

好的，我正在创建这个文字冒险游戏。为了与众不同，我决定添加一个影响系统，您对其他角色的反应可以影响他们对您的反应以及他们的战斗力。 我在 C++ 方面有相当多的经验，而且我刚刚开始了第二个学期的 C 课程。到目前为止，我已经尝试过使用全局变量、结构、静态变量以及在其他函数中使用函数。我也尝试过使用指针，但每次我都会出错，所以我停止了。这是一段尝试使用影响力系统的代码（对不起星星，不想泄露任何故事情节）：

#include <stdlib.h>
#include <stdio.h>
static int positive_Influence; int negative_Influence; int overall_Influence;

void printpInI(int positive_Influence, int negative_Influence);//positive and negative influence

int choice_6()

    int choice = 0;
    int positive_Influence, negative_Influence, overall_Influence;

    positive_Influence = 0;
    negative_Influence = 0;
    overall_Influence = 0;

    printf("What do you do?\n");
    printf("\t1. You: ****\n");
    printf("\t2. You: ****\n");
    printf("\t3. You: ****\n");
    do 
    
        scanf_s("%i", &choice);
        switch (choice)
        
            case 1:
                
                    printf("\t****?\n");
                    system("pause");
                    negative_Influence += 10;
                    printf("You lose influence and are now at %i with ****.\n", positive_Influence-negative_Influence);
                    break;
                
            case 2:
                
                    printf("\t****");
                    system("pause");
                    positive_Influence += 10;
                    printf("You gain influence and are now at %i influence with ****.\n", positive_Influence-negative_Influence);
                    break;
                
            case 3:
                
                    printf("**** smiles at this.\n");
                    system("pause");
                    positive_Influence += 10;
                    printf("You gain influence and are now at %i influence with ****.\n", positive_Influence-negative_Influence);
                    break;
                
        
    while(choice != 1 && choice != 2 && choice != 3);
    overall_Influence = positive_Influence-negative_Influence;
    printf("%i\n", overall_Influence);


void story_7()

    printf("Your overall influence is %i\n", overall_Influence);

int main()

    choice_6();
    story_7();
    system("pause");

【问题讨论】：

您实际上并没有说明您的问题。我的意思是根据你的代码说你遇到的实际问题是什么。

【参考方案1】：

您已将overall_influence 声明为全局变量，但也声明为choice_6 中的局部变量。本地声明优先；只需删除它，您应该就可以了。变量positive_influence 和negative_influence 也一样。

【参考方案2】：

您能告诉我您遇到了哪种类型的错误吗？此外，您已经声明了用于计算影响的全局变量，所以为什么您再次在 choice_6 函数中本地声明它，这是您程序中的错误情况，因此局部变量在它们声明的函数中具有比全局变量更高的优先级。所以从函数choice_6中删除声明。

【参考方案3】：

实际上，我真的很愚蠢，因为我忘记了指针是如何工作的（大坝安培！）无论如何，谢谢大家的回复，我真的很感激。我还在开发一个可以使用多个敌人的战斗系统，所以请继续关注我的个人资料，因为我以后可能会有一些问题。如果您想进行 beta 测试，我的电子邮件是 [e-mail] 如果您想玩我目前拥有的东西。当然，这里是完成的代码（对于choice_6 和story_7）请欣赏：

#include <stdlib.h>
#include <stdio.h>


int choice_6(int *influence)

int choice = 0;
    printf("What do you do?\n");
    printf("\t1. You: No. I know absolutely nothing about you. You could be a monster\n");
    printf("\ttoo for all I know! Normal people don't turn into frogs!\n");
    printf("\t2. You: Your right we should keep moving. You can tell me when your\n");
    printf("\tready.\n");
    printf("\t3. You: Okay where do you think should we go then?\n");
    do 
    
        scanf_s("%i", &choice);
        switch (choice)
        
            case 1:
                
                    printf("\tBrie flashes a pained look on her face and you immediately regret saying that.\n");
                    printf("\tBrie: You really think I'm a monster?\n");
                    system("pause");
                    *influence -= 10;
                    printf("You lose influence and are now at %i with Brie.\n", *influence);
                    system("pause");
                    printf("Influence affects characters reactions towards you, their combat effectiveness, and even their allegiances in rare cases.\n");
                    printf("However, depending on the situation, low influence is not always a bad thing...\n");
                    system("pause");
                    printf("\tYou: Your right we should keep moving.\n");
                    break;
                
            case 2:
                
                    printf("\tBrie: Thank you. I'd rather not discuss this my life story in a dark\n");
                    printf("\tdungeon.\n");
                    system("pause");
                    *influence += 10;
                    printf("You gain influence and are now at %i influence with Brie.\n", *influence);
                    system("pause");
                    printf("Influence affects characters reactions towards you, their combat effectiveness, and even their allegiances in rare cases.\n");
                    printf("However, depending on the situation, low influence is not always a bad thing...\n");
                    system("pause");
                    printf("\tYou: I'd have to agree with you there. Let's see what is up these stairs.\n");
                    choice = 2;
                    break;
                
            case 3:
                
                    printf("Brie smiles at this.\n");
                    printf("\tBrie: Well the only way out seems to be these stairs so let's go up.\n");
                    system("pause");
                    *influence += 10;
                    printf("You gain influence and are now at %i influence with Brie.\n", *influence);
                    system("pause");
                    printf("Influence affects characters reactions towards you, their effectiveness in combat, and even their allegiances in rare cases.\n");
                    printf("However, depending on the situation, low influence is not always a bad thing...\n");
                    system("pause");
                    printf("\tYou: Sounds good to me I am quite frankly done with dungeons about now.\n");
                    break;
                
            default:
                
                    printf("Type the number for the choice you want to do\n");
                    system("pause");
                    break;
                
        
    while(choice != 1 && choice != 2 && choice != 3);


int story_7(int influence)

    if (influence > 0)
    
    printf("Brie laughs at this and slowly leans you off her to have both of you crouch.");
    system("pause");
    
    else
    
        printf("Brie: Ugh just get off of me!\n");
        printf("Brie pushes you off her violently and you manage to stay crouched.");
        system("pause");
    


int main()

    int influence = 0;
    // ...
    choice_6(&influence);
    story_7(influence);
    // ...

【参考方案4】：

您应该删除局部变量并使用范围解析运算符来使用您的全局变量 这将解决您的问题。

您还可以在以后想要的任何函数中使用这些变量。