程序因 Visual Studio Ultimate 2013 中的 scanf_s 而崩溃答案

【问题标题】：Program is crashing because of scanf_s in Visual Studio Ultimate 2013程序因 Visual Studio Ultimate 2013 中的 scanf_s 而崩溃
【发布时间】：2016-06-28 19:10:49
【问题描述】：

我刚刚开始学习 C 语言，因为我的大学有一些编程课程。当我们在 Dev C++ 程序中编程时，我从高中开始就对 C 有一点了解。现在我们需要为此使用 Visual Studio，我编写的下一个程序在 Dev C++ 中运行良好，但在输入名称后崩溃。在开发 C++ 中，我从 strcat 和 scanf 中删除了 _s，它运行良好。有人可以帮我解决这个问题吗？这个程序是关于输入一个名字的，它应该随机地将你安排在这两个团队中的一个中。

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

int main() {
    int maxPlayers = 16, player, teamForming, numPlayer1 = 0, numPlayer2 = 0;
    char blueTeam[256] = "", redTeam[256] = "", name[16];
    for (player = 1; player <= maxPlayers; player++) {
        printf("\nEnter a name of %d. player : ", player);
        scanf_s(" %s", name);
        teamForming = rand() % 2;
        if (teamForming == 0) {
            if (numPlayer1 == 8) {
                strcat_s(redTeam, name);
                strcat_s(redTeam, " ");
                numPlayer2++;
                break;
            }
            strcat_s(blueTeam, name);
            strcat_s(blueTeam, " ");
            numPlayer1++;
        } else {
            if (numPlayer2 == 8) {
                strcat_s(blueTeam, name);
                strcat_s(blueTeam, " ");
                numPlayer1++;
                break;
            }
            strcat_s(redTeam, name);
            strcat_s(redTeam, " ");
            numPlayer2++;
        }
    }
    printf("\nBlue team : %s.\n", blueTeam);
    printf("\nRed team : %s.\n", redTeam);
    return 0;
}

【问题讨论】：

我相信scanf_s 需要s、S、c 和C 格式的两个参数。第一个是结果指针（同scanf），第二个是缓冲区大小参数。

标签： c visual-studio scanf dev-c++

【解决方案1】：

scanf_s 和scanf 的语义略有不同：对于s 和[ 格式，您必须传递目标数组的大小：

scanf_s(" %s", name, sizeof(name));

同样，strcat_s 将目标数组和源字符串之间的第三个参数，即目标数组中元素的数量作为第三个参数。

这是您的代码的修改版本：

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

int main(void) {
    int maxPlayers = 16, player, teamForming, numPlayer1 = 0, numPlayer2 = 0;
    char blueTeam[256] = "", redTeam[256] = "", name[16];
    for (player = 1; player <= maxPlayers; player++) {
        printf("\nEnter a name of %d. player : ", player);
        scanf_s(" %s", name, sizeof(name));
        teamForming = rand() % 2;
        if (teamForming == 0) {
            if (numPlayer1 == 8) {
                strcat_s(redTeam, sizeof(redTeam), name);
                strcat_s(redTeam, sizeof(redTeam), " ");
                numPlayer2++;
                break;
            }
            strcat_s(blueTeam, sizeof(blueTeam), name);
            strcat_s(blueTeam, sizeof(blueTeam), " ");
            numPlayer1++;
        } else {
            if (numPlayer2 == 8) {
                strcat_s(blueTeam, sizeof(blueTeam), name);
                strcat_s(blueTeam, sizeof(blueTeam), " ");
                numPlayer1++;
                break;
            }
            strcat_s(redTeam, sizeof(redTeam), name);
            strcat_s(redTeam, sizeof(redTeam), " ");
            numPlayer2++;
        }
    }
    printf("\nBlue team : %s.\n", blueTeam);
    printf("\nRed team : %s.\n", redTeam);
    return 0;
}

【讨论】：