【项目1-由键盘到文件】
（1）从键盘输入一个文件名，以及一个以#结束的字符序列，将输入的字符保存到文件中去。
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE *fp ;
char ch,fname[10];
printf("文件名:");
gets(fname);
if ((fp=____(1)____)==NULL)
{
printf("connot open\n");
exit(0);
}
while ((ch=getchar())!='#')
fputc(____(2)____);
____(3)____;
return 0;
}[参考解答]
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE *fp ;
char ch,fname[10];
printf("文件名:");
gets(fname);
if ((fp=fopen(fname, "w"))==NULL) //(1)
{
printf("connot open\n");
exit(0);
}
while ((ch=getchar())!='#')
fputc(ch,fp); //（2）
fclose(fp); //(3)
return 0;
}
（2）设上题建立了名为f1.dat的文件，请将这个文件拷贝到一个名为f2.dat的文件中。
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE *fp1,*fp2 ;
char c;
if (（fp1=fopen("f1.dat", ___(1)___)）==NULL)
{
printf("connot open\n");
exit(0);
}
if (（fp2=fopen("f2.dat", ___(2)___)）==NULL)
{
printf("connot open\n");
exit(0);
}
c=fgetc(fp1);
while (___(3)___)
{
fputc(c,fp2);
c=fgetc(fp1);
}
___(4)___
return 0;
}[参考解答]
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE *fp1,*fp2 ;
char c;
if ((fp1=fopen("f1.dat", "r"))==NULL) //(1)
{
printf("connot open\n");
exit(0);
}
if ((fp2=fopen("f3.dat", "w"))==NULL) //(2)
{
printf("connot open\n");
exit(0);
}
c=fgetc(fp1);
while (c!=EOF) //(3)：或者!feof(fp1)，feof函数用于检查是否到达文件尾
{
fputc(c,fp2);
c=fgetc(fp1);
}
fclose(fp2); fclose(fp1); //(4)
return 0;
}
（3）以下程序的功能是将文件file1.dat的内容输出到屏幕上并复制到文件file2.dat中，请补充完整。
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE ___(1)___;
char ch;
fp1=fopen("file1.dat","r");
fp2=fopen("file2.dat","w");
while (!feof(fp1))
{
ch=___(2)___;
putchar(ch);
fputc(___(3)___);
}
fclose(fp1);
fclose(fp2) ;
return 0;
}[参考解答]
#include "stdio.h"
#include "stdlib.h"
int main()
{
FILE *fp1, *fp2; //(1)
char ch;
fp1=fopen("file1.dat","r");
fp2=fopen("file2.dat","w");
while (!feof(fp1))
{
ch=fgetc(fp1); //(2)
putchar(ch);
fputc(ch, fp2); //(3)
}
fclose(fp1);
fclose(fp2) ;
return 0;
}
