c的底层函数实现.cpp

this a map to you updata myself

//需要用的C的底层函数实现：login ,dir,create,delete,open,close,read,write等功能。


#include<fstream.h> 
#include<conio.h> 
#include<iostream.h> 
#include<string.h> 
#include<process.h> 
#include<stdlib.h> 

class employee 
{ 
public: 
char empname[20]; 
char empid[20]; 
char age[20]; 
char salary[20]; 
char dept[20]; 
char post[20]; 
public: 
void get(); 

}; 

void employee::get() 
{ 
cout<<"enter employee name\n"; 
cin>>empname; 
cout<<"enter employee id\n"; 
cin>>empid; 
cout<<"enter employee age \n"; 
cin>>age; 
cout<<"enter employee salary\n"; 
cin>>salary; 
cout<<"enter employee department \n"; 
cin>>dept; 
cout<<"enter employee post \n"; 
cin>>post; 
} 

void menu() 
{ 
int i,j,k,flag=0,choice; 
void space(); 
void create(); 
void read(); 
void copy(); 
void search(); 
void append(); 
void deletion(); 
clrscr(); 
cout<<"\n\n\n"; 
for(i=0;i<80;i++) 
cout<<"*"; 
for(i=1;i<=3;i++) 
{ 
cout<<"\n"; 
for(j=0;j<80;j++) 
{ 
if(j<29||j>51) 
cout<<"*"; 
else 
{ 
if(i==2&&flag==0) 
{ 
cout<<" Employees Database "; 
flag=1; 
for(k=1;k<=28;k++) 
cout<<"*"; 
break; 
} 
else 
cout<<" "; 
} 
} 
} 
cout<<"\n"; 
for(i=0;i<80;i++) 
cout<<"*"; 
cout<<"\n\n\n\n\n\n"; 
space(); 
for(j=1;j<=22;j++) 
cout<<"-"; 
cout<<"\n"; 
space(); 
cout<<"| (1). Create file |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (2). Read data |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (3). Copy data |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (4). Search record |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (5). Append data |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (6). Delete record |"; 
cout<<"\n"; 
space(); 
cout<<"| |"; 
cout<<"\n"; 
space(); 
cout<<"| (7). Exit |"; 
cout<<"\n"; 
space(); 
for(j=1;j<=22;j++) 
cout<<"-"; 
cout<<"\n\n\n\n\n"; 
space(); 
cout<<"\b\b\b\b\b\b\b\bInput the number to indicate choice: "; 
cin>>choice; 
if(choice!=1&&choice!=2&&choice!=3&&choice!=4&&choice!=5&&choice!=6&&choice!=7) 
{ 
cout<<"\n\n\n\n"; 
space(); 
cout<<"Invalid choice"; 
getch(); 
menu(); 
} 
switch (choice) 
{ 
case 1: 
create(); 
break; 
case 2: 
read(); 
break; 
case 3: 
copy(); 
break; 
case 4: 
search(); 
break; 
case 5: 
append(); 
break; 
case 6: 
deletion(); 
break; 
case 7: 
exit(0); 
break; 
} 
} 

void space() 
{ 
int i; 
for(i=1;i<=30;i++) 
cout<<" "; 
} 

void create()//create function 
{ 
char ch='y'; 
employee e; 
ofstream outfile; 
char fname[20]; 
clrscr(); 
cout<<"Enter the name of file to create the records \n"; 
cin>>fname; 
outfile.open(fname,ios::out|ios::binary); 
employee f; 
strcpy(f.empname,"EName:"); 
strcpy(f.empid,"EmpID:"); 
strcpy(f.age,"Age:"); 
strcpy(f.salary,"Salary:"); 
strcpy(f.dept,"Dept:"); 
strcpy(f.post,"Post:"); 
outfile.write((char *)&f,sizeof(f)); 
outfile.close(); 
outfile.open(fname,ios::app|ios::binary); 
while(ch=='y') 
{ 
cout<<"enter a record\n"; 
e.get(); 
outfile.write((char *)&e,sizeof(e)); 
cout<<endl<<"add another record: Y/N: \n"; 
cin>>ch; 
} 
outfile.close(); 
cout<<"\n records entered successfully"; 
getch(); 
menu(); 
} 

void read()//read function 
{ 
employee e; 
ifstream infile; 
char fname[20]; 
clrscr(); 
cout<<"Enter the name of file to display the records \n"; 
cin>>fname; 
infile.open(fname,ios::in|ios::binary); 
cout<<"the records are: \n"; 
while(infile.read((char *)&e,sizeof(e))) 
{ 
cout<<endl<<e.empname<<"\t"<<e.empid<<"\t"<<e.age<<"\t"<<e.salary<<"\t"<<e.dept<<"\t"<<e.post<<endl; 
} 
getch(); 
menu(); 
} 

void append()//append function 
{ 
char ch='y'; 
employee e; 
ofstream outfile; 
char fname[20]; 
clrscr(); 
cout<<"enter the name of file to append the records \n"; 
cin>>fname; 
outfile.open(fname,ios::app|ios::binary); 
while(ch=='y') 
{ 
cout<<"enter new record to append\n"; 
e.get(); 
outfile.write((char *)&e,sizeof(e)); 
cout<<endl<<"add another record: Y/N: \n"; 
cin>>ch; 
} 
outfile.close(); 
cout<<"\n records entered successfully"; 
getch(); 
menu(); 
} 

void copy()//filecopy function 
{ 
char source[20],target[20]; 
employee e; 
clrscr(); 
cout<<"enter source filename\n"; 
cin>>source; 
cout<<"enter target filename\n"; 
cin>>target; 
ifstream in; 
ofstream out; 
in.open(source,ios::in|ios::binary); 
out.open(target,ios::out|ios::binary); 
while(in.read((char *)&e,sizeof(e))) 
{ 
out.write((char *)&e,sizeof(e)); 
} 
in.close(); 
out.close(); 
cout<<"the records are copied successfully \n"; 
getch(); 
menu(); 
} 

void deletion()//delete the record depending on the empname 
{ 
employee e; 
ifstream infile; 
ofstream outfile; 
char fname[20],name[20]; 
int flag=0; 
clrscr(); 
cout<<"Enter the name of file to delete the records \n"; 
cin>>fname; 
cout<<"Enter the employee name to delete \n"; 
cin>>name; 
infile.open(fname,ios::in|ios::binary); 
outfile.open("temp.txt",ios::out|ios::binary); 
while(infile.read((char *)&e,sizeof(e))) 
{ 
if(strcmp(name,e.empname)!=0) 
{ 
outfile.write((char *)&e,sizeof(e)); 
} 
else 
{ 
flag++; 
cout<<endl<<"Deleted the record:"<<endl<<e.empname<<"\t"<<e.empid<<"\t"<<e.age<<"\t"<<e.salary<<"\t"<<e.dept<<"\t"<<e.post<<endl; 
} 
} 
if(infile.eof()&&flag==0) 
{ 
cout<<"No record matched"; 
} 
infile.close(); 
outfile.close(); 
ifstream in; 
ofstream out; 
in.open("temp.txt",ios::in|ios::binary); 
out.open(fname,ios::out|ios::binary); 
while(in.read((char *)&e,sizeof(e))) 
{ 
out.write((char *)&e,sizeof(e)); 
} 
in.close(); 
out.close(); 
getch(); 
menu(); 
} 

void search_name()//search function by empname 
{ 
employee e; 
ifstream infile; 
char name[20],fname[20]; 
clrscr(); 
cout<<"Enter the name of file to search the records \n"; 
cin>>fname; 
infile.open(fname,ios::in|ios::binary); 
cout<<"enter the employee name to search \n"; 
cin>>name; 
int flag=0; 
while(infile.read((char *)&e,sizeof(e))) 
{ 
if(strcmp(name,e.empname)==0) 
{ 
cout<<endl<<e.empname<<"\t"<<e.empid<<"\t"<<e.age<<"\t"<<e.salary<<"\t"<<e.dept<<"\t"<<e.post<<endl; 
flag++; 
//cout<<flag; 
} 
} 
if(infile.eof()&&flag==0) 
{ 
cout<<"no records found"; 
} 
infile.close(); 
getch(); 
menu(); 
} 

void search_id()//search function by empname 
{ 
employee e; 
ifstream infile; 
int flag=0; 
char fname[20],id[20]; 
clrscr(); 
cout<<"Enter the name of file to search the records \n"; 
cin>>fname; 
infile.open(fname,ios::in|ios::binary); 
cout<<"enter the employee id to search \n"; 
cin>>id; 
while(infile.read((char *)&e,sizeof(e))) 
{ 
if(strcmp(id,e.empid)==0) 
{ 
cout<<endl<<e.empname<<"\t"<<e.empid<<"\t"<<e.age<<"\t"<<e.salary<<"\t"<<e.dept<<"\t"<<e.post<<endl; 
flag++; 
//cout<<flag; 
} 
} 
if(infile.eof()&&flag==0) 
{ 
cout<<"no records found"; 
} 
infile.close(); 
getch(); 
menu(); 
} 

void search()//search function 
{ 
int num; 
clrscr(); 
cout<<"Enter the number to select the search function"<<endl<<"\"1\" for searching by employee name"<<endl<<"\"2\" for searching by employee id"<<endl; 
cin>>num; 
if(num==1) 
{ 
search_name(); 
} 
if(num==2) 
{ 
search_id(); 
} 
if(num!=1&&num!=2) 
{ 
cout<<"Invalid Number"<<endl<<"Try again"; 
getch(); 
search(); 
} 
getch(); 
} 


void main() 
{ 
menu(); 
getch(); 
}