Question

我的论文中有一个问题。我有10个员工ID M001，A004，D007等...用户正在输入上述ID中的一个，如果id不存在则打印未找到的ID。我厌倦了strcmp并被卡住了。如果你告诉我一个方法，这很好吗？谢谢，请注意：我是C.的初学者。我正在尝试一种简单的方法，现在它给出了for循环的错误。

下标值既不是数组也不是指针，也不是向量

    #include<stdio.h>
    #include<string.h>
    float tSalary(float salary,float bonus);
    char searchid(char search);
    int main(void)
    {
       char status,input,search,C,P;
       char searchId[8][4]={"M001","A004","D007","D010","D012","Q008","Q015","DE09"};
       float salary,bonus,tSalary;
       int i,j;

       do{
          printf("Enter the employee id: ");
          scanf("%s", &search);
          printf("Enter the job status: ");
          scanf("%s", &status);  
          printf("Enter the salary: ");
          scanf("%f", &salary);

          for(i=0;i<8;i++){              //This is where all things go wrong
             for(j=0;j<4;j++){
                if(searchid[i][j]=search){    //the [i] where the subscripted error occurs 
                   printf("Id is valid\n");
                }
                else printf("Invalid id\n");

             }
          }

        printf("Do you want to enter another record?(Y-Yes/N-No): ");
        scanf(" %c", &input);
        }while(input=='Y'||input=='y');
    return 0;
    }

Answer 1

发布的代码中存在很多问题。对于初学者，searchId应声明为searchId[8][5]，以便在每个字符串末尾为\0终结符腾出空间。

从输入代码中可以看出status和search应该包含字符串，但这些字符串被声明为char s。修复此问题后，请注意在调用这些数组的&调用中不需要地址运算符scanf()。此外，在%s转换说明符与scanf()一起使用时，应始终指定最大宽度，以避免缓冲区溢出。

使用==比较运算符无法比较字符串，因此应在此处使用strcmp()。这可以在循环遍历字符串数组的循环中完成;索引达到8时循环退出，或者比较成功。然后，在循环之后，如果索引已达到8（所有有效的id字符串都未通过测试），则search字符串无效。

以下是已发布代码的修改版本，它实现了所有这些：

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

float tSalary(float salary,float bonus);
char searchid(char search);

int main(void)
{
    char status[1000];
    char search[1000];
    char input, C, P;
    char searchId[8][5] = { "M001", "A004", "D007", "D010",
                            "D012", "Q008", "Q015", "DE09" };
    float salary, bonus, tSalary;
    int i, j;

    do {
        printf("Enter the employee id: ");
        scanf("%999s", search);
        printf("Enter the job status: ");
        scanf("%999s", status);  
        printf("Enter the salary: ");
        scanf("%f", &salary);

        i = 0;
        while (i < 8 && strcmp(search, searchId[i]) != 0) {
            ++i;
        }

        if (i < 8) {
            printf("Id is valid\n");
        } else {
            printf("Invalid id\n");
        }

        printf("Do you want to enter another record?(Y-Yes/N-No): ");
        scanf(" %c", &input);
    } while (input == 'Y' || input == 'y');

    return 0;
}

示例程序交互：

Enter the employee id: A004
Enter the job status: pending
Enter the salary: 2000
Id is valid
Do you want to enter another record?(Y-Yes/N-No): y
Enter the employee id: Q015
Enter the job status: completed
Enter the salary: 3000
Id is valid
Do you want to enter another record?(Y-Yes/N-No): y
Enter the employee id: B001
Enter the job status: completed
Enter the salary: 1200
Invalid id
Do you want to enter another record?(Y-Yes/N-No): n

如何将字符串与用户输入进行比较？

1 个答案: