用C++写的个人资金账户管理

发布网友 发布时间：2022-05-01 07:42

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热心网友 时间：2022-06-26 06:13

#include"stdio.h"
#include"stdlib.h"
long size; /*当前最近一次的流水号*/
struct LogData{ /*记录的结构*/
long logid; /*记录ID*/
char logdate[11]; /*记录发生日期*/
char lognote[15]; /*记录事件说明*/
double charge; /*发生费用：负表示支出，正表示收入*/
double balance; /*余额*/
};

int inputchoice() /*选择操作参数*/
{
int mychoice;
printf("\nEnter your choice:\n");
printf("1-Add a new cash LOG.\n2-List All Cash LOG.\n");
printf("3-Query Last Cash LOG.\n0-End program.\n");
scanf("%d",&mychoice);
return mychoice;
}

long getLogcount(FILE*cfptr) /*获取文件记录总数*/
{
long begin,end,logcount;
fseek(cfptr,0L,SEEK_SET);
begin=ftell(cfptr);
fseek(cfptr,size,SEEK_END);
end=ftell(cfptr);
logcount=(end-begin)/size-1;
return logcount;
}

void ListAllLog(FILE*cfptr) /*列出所有收支流水帐*/
{
struct LogData log;
fseek(cfptr,0L,SEEK_SET); /*定位指针到文件开始位置*/
fread(&log,size,1,cfptr);
printf("logid logdata lognote charge balance\n");
while(!feof(cfptr)){
printf("%6ld%-11s%-15s%10.2lf%10.2lf\n",
log.logid,log.logdata,log.lognote,log.chargge,log.balance);
fread(&log.size,1,cfptr);
};
}

void QueryLastLog(FILE*cfptr) /*查询显示最后一条记录*/
{
struct LogData log;
long logcount;
logcount=getLogcount(cfptr);
if(logcount>0) /*表示有记录存在*/
{
fseek(cfptr,size*(logcount-1),SEEK_SET); /*定位最后记录*/
fread(&log,size,1,cfptr); /*读取最后记录*/
printf("The last log is:\n");
printf("logid:%-6ld\nlogdata:%-11s\nlognote:%-15s\n",
log.logid,log.logdata,log.lognote);
printf("charge:%-10.2lf\nbalance:%-10.2lf\n",
log.charge,log.balance); /*显示最后记录内容*/
}
else printf("no logs in file!\n");
}

void AddNewLog(FILE*cfptr) /*添加新纪录*/
{
struct LogData log,lastlog;
long logcount;
printf("Input logdate(format:2006-01-01):");
scanf("%s",log.logdate);
printf("Input lognote:");
scanf("%s",log.lognote);
printf("Input Charge:Income+and expend-:");
scanf("%lf",&log.charge);
logcount=getLogcount(cfptr); /*获取记录数*/

if(logcount>0){
fseek(cfptr,size*(logcount-1),SEEK_SET);
fread(&lastlog,size,1,cfptr); /*读入最后记录*/
log.logid=lastlog.logid+1; /*记录号按顺序是上次的+1*/
log.balance=log.charge+lastlog.balance;
}
else{ /*如果文件是初始状态，记录数为0*/
log.logid=1;
log.balance=log.charge;
}
rewind(cfptr);
printf("logid=%ld\n",log.logid);
fwrite(&log.sizeof(struct LogData),1,cfptr); /*写入记录*/
}

FILE*openfile(char*openmode) /*打开文件*/
{
FILE*fp;
if((fp=fopen("cashbox.dat",openmode))==NULL){
printf("can not open file cashbox.dat!\n");
exit(0);
}
return(fp);
}
int main(void)
{
FILE*fp;
int choice;
size=sizeof(struct LogData);
while((choice=inputchoice())!=0){
switch(choice){
case1:
fp=openfile("ab+");
AddNewLog(fp);
break;
case2: /*列出所有的收入支出情况*/
fp=openfile("rb");
ListAllLog(fp);
break;
case3: /*查询最后记录及余额*/
fp=openfile("rb");
QueryLastLog(fp);
break;
default:
printf("Input Error.");
break;
}
}
if(fclose(fp)){
printf("Can not close the file!\n");
exit(0);
}
return 0;
}