1 //判断读到文件末尾
2 #include <stdio.h>
3 #define F_PRINT_ERR(e)\
4 do\
5 {\
6 if(e == NULL)\
7 {\
8 printf("open error");\
9 exit(-1);\
10 }\
11 }\
12 while(0)
13 int main(int argc,char* argv[])
14 {
15
16 FILE* pf = fopen("G:/qtcode/pfw.txt","w+");
17 F_PRINT_ERR(pf);
18 //往文件里写几个字符进去
19 char ch;
20 for(ch = 'a';ch <= 'd';ch++)
21 {
22 putchar(fputc(ch,pf));
23 }
24 putchar(10);
25 rewind(pf);
26 //尝试通过两种方式判断读到文件末尾
27 #if 0
28 //错误用法
29 while(!feof(pf))//
30 {
31 ch = fgetc(pf);
32 printf("%x->%c\n",ch,ch);
33 }
34 #endif
35
36 #if 0
37 //正确用法，先读再判断
38 while((ch = fgetc(pf)) && (!feof(pf)))
39 {
40 printf("%x->%c\n",ch,ch);
41 }
42 #endif
43
44 #if 0
45 //正确用法，先读再判断
46 ch = fgetc(pf);
47 while(!feof(pf))
48 {
49 printf("%x->%c\n",ch,ch);
50 ch = fgetc(pf);
51 }
52 #endif
53
54 #if 1
55 while((ch = fgetc(pf)) != EOF)
56 {
57 printf("%x->%c\n",ch,ch);
58 }
59 #endif
60
61 return 0;
62 }
