一个使用 C 的简单计算器，用于将华氏温度转换为摄氏温度，反之亦然

Question

美好的一天！我尝试使用 C 制作一个简单的计算器，用于我的第一个关于华氏到摄氏度之间转换的项目，反之亦然。但它不起作用，有人可以告诉我我想念什么吗？

这是我的代码：

#include <stdio.h>

int main()
{
double temp, fahrenheit, celsius;
char answer[2];

printf("Type 'CF' if you want to convert from celsius to fahrenheit, and 'FC' if you want to convert from fahrenheit to celcius: ");
fgets(answer, 2, stdin);

fahrenheit = (temp * 1.8) + 32;
celsius = (temp - 32) * 0.5556;
if(answer == "CF"){
    printf("Type the temperature here: ");
    scanf("%lf", &temp);
    printf("Answer: %f", fahrenheit);
}
else if(answer == "FC"){
    printf("Type the temperature here: ");
    scanf("%lf", &temp);
    printf("Answer: %f", celsius);
}
return 0;

}

calculator

Answer 1

您不能在 C 中比较这样的字符串。有 strcmp 和 strncmp 函数。除了这个 C 字符串以 \0 符号结尾，所以你的代码应该是这样的：

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

int main()
{
    double temp, fahrenheit, celsius;
    char answer[3];

    printf("Type 'CF' if you want to convert from celsius to fahrenheit, and 'FC' if you want to convert from fahrenheit to celcius: ");
    fgets(answer, 3, stdin);

    fahrenheit = (temp * 1.8) + 32;
    celsius = (temp - 32) * 0.5556;

    if (strcmp(answer, "CF") == 0) {
        printf("Type the temperature here: ");
        scanf("%lf", &temp);
        printf("Answer: %f", fahrenheit);
    } else if (strcmp(answer, "FC") == 0){
        printf("Type the temperature here: ");
        scanf("%lf", &temp);
        printf("Answer: %f", celsius);
    }

    return 0;
}

Answer 2

将strcmp 用于

(answer == "CF"){

即

strcmp(answer, "CF") == 0