#include <stdio.h>
#define MAXLEN 100
#define MAXLINE 100
char Buffer[MAXLEN],filename[128];
char *LinePointer[MAXLINE]; /*定义字符指针数组来存储要编辑的文本行指针*/
int Modified=0; /*正文被修改标志*/
int LineNum; /*当前正文行数*/
char *CmdPointer; /*输入命令行字符指针*/
void Quit() 退出
{
int i;
char c;
if(Modified==1) /* 如正文被修改,则提示用户是否要保存*/
{
printf("Save or not? (y/n):");
scanf("%c",&c);
if(c==y||c==Y) /* 保存被修改过的正文 */
Save();
}
for(i=0;i<LineNum;i++) /* 释放内存 */
free(LinePointer[i]);
}
void Insert()
{
int k,m,i;
sscanf(CmdPointer,"%d%d",&k,&m); /* 读入参数 */
for(i=LineNum;i>m;i--) /* 后继行向后移 */
LinePointer[i+k-1]=LinePointer[i-1];
for(i=0;i<k;i++) /* 读入k行正文，并插入到指针数组，待写入文件*/
{
fgets(Buffer,MAXLEN,stdin);
LinePointer[m+i]=(char *)malloc(strlen(Buffer)+1);
strcpy(LinePointer[m+i],Buffer);
}
LineNum+=k; /* 修正正文行数及设置正文被修改标志*/
Modified=1;
}
void Delete()
{
int i,j,m,n;
sscanf(CmdPointer,"%d%d",&m,&n); /* 读入参数 */
if(n>LineNum)
n=LineNum;
for(i=m;i<=n;i++) /* 删除正文 */
free(LinePointer[i-1]);
for(i=m,j=n+1;j<=LineNum;i++,j++)
LinePointer[i-1]=LinePointer[j-1];
LineNum=i-1; /* 修正正文行数及设置正文被修改标志*/
Modified=1;
}
int Save() /* 保存文件 */
{
int i;
FILE *fp;
if((fp=fopen(filename,"w"))==NULL)
{
printf("Cant open the %s.\n",filename);
return 0;
}
for(i=0;i<LineNum;i++)
{
fputs(LinePointer[i],fp);
free(LinePointer[i]);
}
fclose(fp);
return 1;
}
void Edit() /* 编辑命令函数*/
{
int i;
FILE *fp;
/*读入文件名*/
sscanf(CmdPointer,"%s",filename);
/* 以读的方式打开文件*/
if((fp=fopen(filename,"r"))==NULL)
{/* 如不存在，则创建文件 */
fp=fopen(filename,"w");
fclose(fp);
fp=fopen(filename,"r");
}
i=0;
while(fgets(Buffer,MAXLEN,fp)==Buffer)
{
LinePointer[i]=(char *)malloc(strlen(Buffer)+1);
strcpy(LinePointer[i++],Buffer);
}
fclose(fp);
LineNum=i;
}
int main()
{
int j,flag=0,flag2=0;
LineNum=0;
clrscr();
while(1)
{ printf("\n*************************************************************\n");
printf("| e+filename:Edit (open and display) |\n");
printf("| i+k+m:Insert (insert k lines follow the row of m ) |\n");
printf("| d+m+n :Delete (delete the line from m to n ) |\n");
printf("| q :Quit (leave the system) |\n");
printf("*************************************************************\n");
printf("Please input a command:\n");
gets(Buffer); /*读入命令行*/
for(CmdPointer=Buffer;(*CmdPointer== )||(*CmdPointer==\t);CmdPointer++);
/*掠过空白符*/
if(*CmdPointer==\0) /*空行重新输入*/
continue;
switch(*CmdPointer)
{
case e: /*调用编辑函数*/
CmdPointer++; /*掠过命令符，指向参数*/
Edit();
break;
case i: /*调用插入函数*/
CmdPointer++;
Insert();
break;
case d: /*调用删除函数*/
CmdPointer++;
Delete();
break;
case q: /*调用退出函数*/
flag2=1;
Quit();
break;
default: /*非法命令符*/
flag=1;
break;
}
if(flag==1)
continue;
printf("The text of the file %s is:\n",filename); /*显示正文*/
for(j=0;j<LineNum;j++)
fputs(LinePointer[j],stdout);
if(flag2==1)
break;
}
return 0;
}
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