Question

#include "stdafx.h"
#include "string.h"
#include "stdio.h"
void CharReadWrite(FILE *fin);
FILE *fptr2;

int _tmain(int argc, _TCHAR* argv[])
{   

    char filename[]="ReadMe.txt";
    if (fopen_s( &fptr2, filename, "r" ) != 0 )
      printf( "File stream %s was not opened\n", filename );
    else
      printf( "The file %s was opened\n", filename );
    CharReadWrite(fptr2);
    fclose(fptr2);
    return 0;
    }
void CharReadWrite(FILE *fin){
    int c;
    while ((c=fgetc(fin)) !=EOF) {
        putchar(c);}
}

Answer 1

您正在打开ReadMe.txt进行撰写：

fopen_s( &fptr2, filename, "w" )

然后将其传递给CharReadWrite：

CharReadWrite(fptr2);

试图从中读取：

c=fgetc(fin)

您是否打算将"r"传递给fopen_s来打开它进行阅读？

如果打开ReadMe.txt失败，您也会继续并致电CharReadWrite。

Answer 2

一个问题是，即使您未能打开它，也会尝试阅读（然后关闭）fptr2。

尝试：

#include "stdafx.h"
#include "string.h"
#include "stdio.h"
void CharReadWrite(FILE *fin);
FILE *fptr2;

int _tmain(int argc, _TCHAR* argv[])
{   

    char filename[]="ReadMe.txt";
    if (fopen_s( &fptr2, filename, "w" ) != 0 )
    {
      printf( "File stream %s was not opened\n", filename );
    }
    else
    {
      printf( "The file %s was opened\n", filename );
      CharReadWrite(fptr2);
      fclose(fptr2);
    }
    return 0;
}

Answer 3

问题在于这一行：

if（fopen_s（＆amp; fptr2，filename，“w”）！= 0）

当你传递'w'标志时，"Create an empty file for writing. If a file with the same name already exists its content is erased and the file is treated as a new empty file."

相反，请使用“r +”标记。

Answer 4

你正在打开文件写作并尝试从中读取（fgetc）......

我的文件指针设置错了吗？

4 个答案: