eclipse 带有 switch 语句的交互式菜单

interactive menu with switch statement

提问by uplearnedu.com

Hi I'm trying to make an interactive menu with switch statement in C. Though I'm unsure of how to trigger a function that has certain arguments. I'm a total beginner and I'm stumped how to do this. The function in the switch statement needs the arguments though I would like the function to ask for the numbers. I'm doing this as an assignment and cannot provide the actual code so I made this mock up. Thank you for your help.

嗨，我正在尝试使用 C 语言中的 switch 语句制作一个交互式菜单。虽然我不确定如何触发具有某些参数的函数。我是一个完全的初学者，我很难过如何做到这一点。switch 语句中的函数需要参数，尽管我希望函数要求输入数字。我把它作为一项任务来做，不能提供实际的代码，所以我做了这个模型。感谢您的帮助。

Here is an example of code I might use.

这是我可能会使用的代码示例。

#include <stdio.h>

void printMenu()
{
    int choice;

    do
    {
        printf("Main Menu:\n");
        printf("1) do this\n");
        scanf("%d", &choice);

        switch (choice)
        {
            case 1:
                function(); /* though this needs the arguments */
                break;
        }
    } while (choice != 7);

    int main(void)
    {
        printMenu();
        return 0;
    }

    void function(int number1, float number2)
    {
        /*calculation*/
        printf("enter your numbers");
        /* Not sure how to read the numbers in here */
        printf("%d + %d = %d", number1, number2, number1 + number2);
        return;
    }

回答by AusCBloke

If you want the switchto be as minimal as possible then just call another function which takes in input and then calls the function...

如果您希望switch尽可能小，那么只需调用另一个接收输入的函数，然后调用该函数...

case 1:
   read_input_and_function()
   break;

...

void read_input_and_function(void)
{
   printf("Enter your numbers: ");
   /* scanf number1, number2 */
   function(number1, number2);
}

回答by Barath Ravikumar

The function in the switch statement needs the arguments though I would like the function to ask for the numbers.

switch 语句中的函数需要参数，尽管我希望函数要求输入数字。

How about asking the arguments first , and then calling the function. This way the two arguments can be declared once and be used in other functions of the same switch , but be defined according to the chosen case.

如何先询问参数，然后调用函数。这样，两个参数可以声明一次，并在同一 switch 的其他函数中使用，但根据选择的情况进行定义。

void function1(int, float);

   void printMenu()
   {

     int choice = 0 , num1 = 0;
     float num2 = 0;

     do
      {
          printf("Main Menu:\n");
          printf("1) do this\n");
          scanf("%d", &choice);

          switch (choice)
          {
              case 1:
                  printf("\nEnter number 1\n");
                  scanf("%d",&num1);
                  printf("\nEnter number 2\n");
                  scanf("%f",&num2);
                  function1(num1,num2);
                  break;
          }
      } while (choice != 7);
    }

回答by ricdnts

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

#define Pi 3.14159216

/*  
*small program of how to create a menu
*/

main ()
{
float degree,radians;
int input;
/*degrees to radians */
float degreesToRadians (float deg)
{
return ((Pi * deg) / 180.0);
}

/*radians to degrees*/
float radiansToDegrees (float rad)
{
 return rad * (180 / Pi);
}
void menu ()
{
 printf ("\n");
 printf ("1. degrees\n");
 printf ("2. radians\n");
 printf ("3. quit\n");
do
switch (input) {
case 1:
          printf ("\n");
          printf ("\n");

          printf (" Enter value of degrees: ");
          scanf ("%f", &degree);
          printf ("RADIANS = %f \n\n", degreesToRadians (degree));
          menu (); 
          break;

case 2:
          printf ("\n");
          printf ("\n");

          printf (" Enter value of radians: ");
          scanf ("%f", &radians);
          printf ("DEGREES = %f \n\n", radiansToDegrees (radians));
          menu (); 
          break;
case 3:
          printf (" quiting app \n");
          exit (0);
          break;
default:
      printf ("wrong option\n");
      break;
  }
while (input != 3);
    getchar ();   
   }
 }
menu ();
}