/*
L.Load();函数里面
判断文件不存在后，执行后面的语句，指针异常
*/
#includeiostream
#includestring
#includefstream
usingnamespacestd;
classLogin_Info
{
stringID;//账号
stringPassword;//密码
intRating;//权限
classLogin_Info*next;
friendclassRegister_Info;//设置类Register_Info为友元类
public:
Login_Info():ID(\"tietuo\"),Password(\"16030\"){};
};
classRegister_Info
{
Login_Info*head;
intflag;
public:
intrating;
Register_Info():head(NULL),flag(0){}
~Register_Info(){}
voidInit();//链表初始化
intLen();
voidSave();//保存用户账号信息
voidLoad();
boolRegister();//添加新用户
boolRegister_Info::Find(Login_Info*//查找链表中用户名和密码都相符的位置
boolChange_Pass();//修改用户密码
boolLogin(int//用户登录
voidMenu(int//登陆界面
intGet_flag(){returnflag;}
};
Register_InfoL;
voidRegister_Info::Init()
{
head=newLogin_Info;
head-next=NULL;
}
intRegister_Info::Len()
{
intnum=0;
Login_Info*pt;
pt=head;
while(pt)
{
num;
pt=pt-next;
}
returnnum;
}
voidRegister_Info::Save()
{
intLEN;
fstreamfp;
Login_Info*pt;
pt=head;
LEN=Len();
fp.open(\"Register_Information.txt\");
if(fp.fail())
cerr\"打开文件失败！\"endl;
fpLENendl;
while(pt)
{
fppt-ID\"\\t\"pt-Password\"\\t\"pt-Ratingendl;
pt=pt-next;
}
fp.close();
}
voidRegister_Info::Load()
{
intLEN;
fstreamfp;
Login_Info*p,*q;
fp.open(\"Register_Information.txt\");
if(fp.fail())
cerr\"打开文件失败！\"endl;
else
{
fpLEN;
p=head;
for(inti=0;iLEN;i)
{
q=newLogin_Info;
fpq-IDq-Passwordq-Rating;
p-next=q;
p=p-next;
}
q-next=NULL;
fp.close();
}
}
boolRegister_Info::Register()
{
Login_Info*p,*q,*r;
stringst1,st2,st3;
intst4;
intn;
p=head;
while(p-next)
p=p-next;
q=newLogin_Info;
while(1)
{
cout\"增加新用户\"endl;
cout\"********************************\"endl;
cout\"用户名：\";
cinst3;
r=head;
while(st3!=r-IDnext;
if(st3==r-ID)
{
cout\"该用户名已存在，请重新输入！\"endl;
continue;
}
cout\"密码:\";
cinst1;
cout\"密码确认\";
cinst2;
if(st1!=st2)
{
cout\"两次输入的密码不一致！\"endl;
continue;
}
cout\"用户权限(1.老师，2.学生):\"endl;
cinst4;
cout\"********************************\"endl;
cout\"请选择：(1.注册，2.退出)\"endl;
cinn;
if(n==1)
{
q-ID=st3;
q-Password=st1;
q-Rating=st4;
flag=1;
returntrue;
}
elseif(n==2)
returnfalse;
else
{
cout\"输入有误！请重新输入\"endl;
returnfalse;
}
}
}
boolRegister_Info::Find(Login_Info*
p=head;
while((str1!=p-ID||str2!=p-Password)next;
if(p!=NULL)
{
q=p;
returntrue;
}
else
returnfalse;
}
boolRegister_Info::Change_Pass()
{
stringstr1,str2,str3,str4;
Login_Info*s=NULL;
cout\"更改密码\"endl;
cout\"********************************\"endl;
cout\"用户名:\";
cinstr1;
cout\"旧密码:\";
cinstr2;
if(Find(s,str1,str2))
{
while(1)
{
cout\"新密码:\";
cinstr3;
cout\"密码确认:\";
cinstr4;
if(str3==str4)
{
s-ID=str1;
s-Password=str3;
flag=1;
returntrue;
}
else
cout\"两次输入的密码不一致！\"endl;
}
}
else
{
cout\"用户名和密码不正确！\"endl;
returnfalse;
}
}
boolRegister_Info::Login(int
stringst1,st2;
cout\"用户名:\";
cinst1;
cout\"密码:\";
cinst2;
if(Find(s,st1,st2))
{
L_rating=s-Rating;
returntrue;
}
else
returnfalse;
}
voidRegister_Info::Menu(int
while(1)
{
system(\"cls\");
cout\"成绩查询系统登录页面\"endl;
cout\"**********************************************\"endl;
cout\"1.登陆2.游客身份\"endl;
cout\"3.注册4.修改密码\"endl;
cout\"5.退出\"endl;
cout\"**********************************************\"endl;
cini;
if(i==1)
{
system(\"cls\");
Login(M_rating);
break;
}
elseif(i==2)
{
M_rating=0;
break;
}
elseif(i==3)
{
system(\"cls\");
Register();
}
elseif(i==4)
{
system(\"cls\");
Change_Pass();
}
elseif(i==5)
exit(0);
else
cerr\"选择有误!\"endl;
}
}
intmain(intargc,int*argv[])
{
intrating;
L.Load();
L.Menu(rating);
if(L.Get_flag())
L.Save();
cout\"权限:\"ratingendl;
return0;
} |
