Question

下面的代码告诉我：

3276560 January
3276560 February
3276560 March
3276560 April
3276560 May
3276560 June
3276560 July
3276560 August
3276560 September
3276560 October
3276560 November
3276560 December

但我期待

1 January
2 February
3 March
4 April
5 May
6 June
7 July
8 August
9 September
10 October
11 November
12 December

我的错误在哪里？

#include <stdio.h>

int main(void){

int i;
char a[10], b[10];
char *ptrMonths[] ={"January","February","Mach","April","May","June", "July","August","September","October","November","December"};
FILE *ptrToMonthFile;
ptrToMonthFile=fopen("Monthsrr.txt", "w");

for (i = 0; i < 12; i++)
{
    fprintf(ptrToMonthFile, "%d %s\n", i+1, ptrMonths[i]);
}

fclose(ptrToMonthFile);

ptrToMonthFile=fopen("Monthsrr.txt", "r");

for (i = 0; i < 12; i++)
{       
    fscanf(ptrToMonthFile,"%d %s\n", a, b);
    fprintf(stdout, "%d %s\n", a, b);
}

fclose(ptrToMonthFile);

getch();
}

Answer 1

几个问题：

a的类型必须是int，因为您使用%d读取它。

int a;
char b[10];

您需要将地址传递给fscanf：

fscanf(ptrToMonthFile,"%d %s\n", &a, b);

此外：您还应该检查所有文件功能的返回值。任何I / O都可能失败。

Answer 2

for (i = 0; i < 12; i++)
{       
    fscanf(ptrToMonthFile,"%s %s\n", a, b);
    fprintf(stdout, "%s %s\n", a, b);
}

我已将％d更改为％s＆＃39; s现在有效。

Answer 3

 fprintf(stdout, "%d %s\n", i+1, ptrMonths[i]);

Answer 4

如果你想用％d读它，那么

应该是int。如果您想将其作为字符串读取，请改用％s。

为什么下面的代码给出了不同于预期的输出？

4 个答案: