#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<conio.h>
#define LEN sizeof(struct info)
struct info
{
	char word[40];
	char mean[40];
};
struct info inf[400];
int m=0;
void enter();
void add();
void Delete();
void Edit();
void enter()
{
	int i,m=0;
	char n;
	char to[40];
	printf("请输入单词: ");
	scanf("%s",to);
	FILE *fp;
	if((fp=fopen("data.txt","ab+"))==NULL)
	{
		printf("文件不存在!\n");
		exit(1);
	}
	while(!feof(fp))
	{
		if(fread(&inf[m],LEN,1,fp)==1)
		{
			if(strcmp(to,inf[m].word)==0)
			{
				printf("%s    ",to);
			    printf("%s\n",inf[m].mean);
			    printf("是否继续?");
			    printf("按Y或y表示继续,按其它键返回\n"); 
			    fclose(fp);
			    return;
		    }
		}
		m++;
	}
	printf("无此单词!\n");
	printf("是否继续?");
	printf("按Y或y表示继续,按其它键返回\n"); 
	fclose(fp);
	return;
	if(m==0)
	printf("文件中无记录!\n");
	if((fp=fopen("data.txt","ab+"))==NULL)
	{
		printf("文件不存在!\n");
		return;
	}
	fclose(fp);
}
void add()
{
	int i;
	char n[20];
	FILE *fp;
	if((fp=fopen("data.txt","ab+"))==NULL)
	{
		printf("文件不存在!\n");
		exit(0);
	}
	printf("请输入单词: \n");
	scanf("%s",n);
	while(!feof(fp))
	{
		if(fread(&inf[m],LEN,1,fp)==1)
		{
			if(strcmp(n,inf[m].word)==0)
			{
				printf("已有此单词，是否进行修改?\n");
				printf("1. 是 2. 否\n");
				scanf("%d",&i);
				switch(i)
				{
					case 1:
						Edit();
					case 2:						
						break;
				}
			    printf("是否继续增添?");
			    printf("按Y或y表示继续,按其它键返回\n"); 
			    fclose(fp);
			    return;
		    }
		}
		m++;
	}
	printf("请输入释义：\n");
	scanf("%s",inf[m].mean);
	strcpy(inf[m].word,n);
	if(fwrite(&inf[m],LEN,1,fp)!=1)
	{
		printf("不能保存"); 
	}
	else
	{
	printf("已保存\n是否继续添加？");
	printf("按Y或y表示继续,按其它键返回\n");
	}
	fclose(fp);	
}


void Delete()
{
	FILE *fp,*ft;
	char n[40],k[40];
	int m=0,l=0,i;
	printf("请输入要删除的单词：\n");
	scanf("%s",n); 
	fp=fopen("data.txt","rb+");
	ft=fopen("123.txt","wb+");
	if(fp==NULL||ft==NULL)
	{
		printf("文件不存在!\n");
		exit(1);
	}
		printf("是否删除此单词？谨慎考虑！\n");
		printf("\t1.是");
		printf("\t\t2.否\n");
		scanf("%d",&i); 
		switch(i)
		{
		case 1:
		while(fread(k,sizeof(k),1,fp))
		{
			if(strcmp(k,n)!=0)
			{
				fwrite(k,sizeof(k),1,ft);
				m++;
			}
			else
			{
				rewind(fp);
				fseek(fp,sizeof(k)*(m+2),0);	
			}
		}
		fclose(fp);
		fclose(ft);
		remove("data.txt");
		rename("123.txt","data.txt");
		printf("删除成功");
		break;
		case 2:break;
	}	
		printf("是否继续?\n");
		printf("按Y或y表示继续,按其它键返回\n");
		return;
}
void Edit()
{
	int t,a,m=0;
	char n[40],k[40];
	FILE *fp;
	printf("请输入要修改的单词：");	
	scanf("%s",n);
	if((fp=fopen("data.txt","rb+"))==NULL)
	{
		printf("文件不存在!\n");
		exit(1);
	}
	rewind(fp);
	while(!feof(fp))
	{ 
	if(fread(&inf[m],LEN,1,fp)==1)
	if(strcmp(n,inf[m].word)==0)
	{
		printf("是否修改释义？\n");
		printf("\t1.是.");
		printf("\t\t2.否.\n");			
		scanf("%d",&a);
		switch(a)
		{
		case 1:printf("请输入修改后的释义：");
		scanf("%s",k);
		strcpy(inf[m].mean,k);
		t=sizeof(inf[m].mean);
		fseek(fp,-t,1);
		if(fwrite(&inf[m].mean,t,1,fp)==1)
		printf("修改成功!");
		break;
		case 2:
		break;
		}
		printf("是否继续?\n");
		printf("按Y或y表示继续,按其它键返回\n");
		fclose(fp);	
		return;
	}
	m++;
    }
	printf("无此单词\n");
	printf("是否继续修改?\n");
	printf("输入y或Y继续操作，输入其他返回菜单\n");
	fclose(fp);
	return;
}
int main(void)
{
int choice;
char n[2];
do
{
printf("\n\t           ==============================");
printf("\n\t           *欢迎使用有限规模电子英汉词典*");
printf("\n\t           ==============================\n");
printf("\n\t           ***********菜单显示***********\n");
printf("\n\t           ********【1】词条查找*********\n");
printf("\n\t           ********【2】词条增词*********\n");
printf("\n\t           ********【3】词条删除*********\n");
printf("\n\t           ********【4】词条修改*********\n");
printf("\n\t           ********【0】退出词典*********\n"); 
printf("请选择你要进行的功能：");
scanf("%d",&choice);
switch(choice)
{
	case 1:
	   enter();
	   scanf("%s",&n);
	   while(n[0]=='Y'||n[0]=='y')
	   {
		  enter();
		  scanf("%s",&n);
	   } 
	   break;
	case 2:
	   add();
	   m++;
       scanf("%s",&n);
       while(n[0]=='Y'||n[0]=='y')
	   {
		  add();
		  m++; 
		  scanf("%s",&n);
	   }
 	   break;
	case 3:
	   Delete();
	   scanf("%s",&n);
	   while(n[0]=='Y'||n[0]=='y')
	   {
		  Delete();
		  scanf("%s",&n);
	   } 
	   break;
	case 4:
	   Edit();
	   scanf("%s",&n);
	   while(n[0]=='Y'||n[0]=='y')
	   {
		  Edit();
		  scanf("%s",&n);
	   } 
	   break;
	}	
}while(choice!=0);
return 0;
}