我需要一个功能，我可以禁止字符输入，我只需要用户的整数输入

Question

case 'f': 
      printf ("Great!!! lets create your fixed account\n"); 

     printf ("\nA minimum purchase of 1000 units is required for this 

account\n"); 
      printf ("\nPrice per unit as of Sep. 15 is $52.69\n") 
; 
      printf ("\nPlease enter required amount of units\n"); 

      scanf("%d",&amount); 


      if (isdigit(amount)) 

       { 
       printf ("invalid input\n"); 
       success = 'f'; 
       break; 

Answer 1

阅读doc on scanf，然后更改您的代码以检查您的调用scanf的返回值。如果用户输入的值与当前代码页中的字符匹配，则数字（金额）只能成功，因此请停止调用它。