c - 将字符保存在数组中

Question

我想做一个程序，要求用户提供一个字符，然后输入...直到他想通过按 Enter 键停止并且没有字符。

然后，程序会说:“你给了角色......”

例如:

give the caracter 1: k + enter
give the caracter 2: l + enter
give the caracter 3: just enter ('\n')

结果:您给出的字符:kl

我的代码不能工作，因为当我按下回车键时，什么也没有发生。这是代码:

#include <stdio.h>
#define N 1000

int main() {

    int i = 0;
    int j = 0;
    char str[N];

    while (str[i] != '\n') {
        printf("element number str[%d] : ", i);
        scanf("%s", &str[i]);
        i++;
    }

    printf("The string is: ");

    while (j < i) {

        printf("%s", str[j]);
        j += 1;
    }

    return 0;
}

Answer 1

您可以使用c = getchar();或c = fgetc(stdin)函数来实现:

#include <stdio.h>
#define N 1000

int
main ()
{
  int i = 0;
  int j = 0;
  int c;

  char str[N];

  while (1)
  {
    c = fgetc(stdin); // or c = getchar();

    if ( (c != EOF) && (c != 0x0A ) ) // 0x0A = 'nl' character
    {
      str[i] = (char) c;
      printf ("element number str[%d]=%c \n", i, str[i++] );
    }
    else 
    {
     str[i] = 0;  
     break;
    }

  }

  printf ("The string is: %s", str);

  return 0;
}

输出:

This is my string!                                                                                                                                                                                                                                
element number str[1]=T                                                                                                                                                                                                                           
element number str[2]=h                                                                                                                                                                                                                           
element number str[3]=i                                                                                                                                                                                                                           
element number str[4]=s                                                                                                                                                                                                                           
element number str[5]=                                                                                                                                                                                                                            
element number str[6]=i                                                                                                                                                                                                                           
element number str[7]=s                                                                                                                                                                                                                           
element number str[8]=                                                                                                                                                                                                                            
element number str[9]=m                                                                                                                                                                                                                           
element number str[10]=y                                                                                                                                                                                                                          
element number str[11]=                                                                                                                                                                                                                           
element number str[12]=s                                                                                                                                                                                                                          
element number str[13]=t                                                                                                                                                                                                                          
element number str[14]=r                                                                                                                                                                                                                          
element number str[15]=i                                                                                                                                                                                                                          
element number str[16]=n                                                                                                                                                                                                                          
element number str[17]=g                                                                                                                                                                                                                          
element number str[18]=!                                                                                                                                                                                                                          
The string is: This is my string!                                                                                                                                                                                                                 

或者您可以使用原来的 scanf("%s", &str1);

#include <stdio.h>
#define N 1000

int main ()
{
    int i = 0;
    int k = 0;
    int c;
    int len;

    char str[N];
    char str1[N];

    scanf("%s", &str1);

    len = strlen(str1); 

    for(k = 0; k < len; k++)
    {
       c = str1[k];     

       if ( (c != EOF) && c != '\n') // EOF will work for ^D on UNIX
       {
          str[i] = (char) c;
          printf ("element number str[%d]=%c \n", i, str[i++] );
       }
       else 
       {
         str[i] = 0;  
         break;
       }
    }   

    printf ("The string is: %s", str);

    return 0;
}

输出:

12345                                                                                                                                                                                                                                             
element number str[1]=1                                                                                                                                                                                                                           
element number str[2]=2                                                                                                                                                                                                                           
element number str[3]=3                                                                                                                                                                                                                           
element number str[4]=4                                                                                                                                                                                                                           
element number str[5]=5                                                                                                                                                                                                                           
The string is: 12345