Thread: files fstream function iin c++

i have the following code and im trying the following: i need to clear the file data and insert data in the cleared file on the other hand i need to read the file information the following is the code i m using and im facing problems as the file is not cleared and i dont n=know what i should do any help is really appreciated thank in advnace

Code:

#include<iostream>#include <fstream>
using namespace  std;
#include "Cboard.h"
#include "Cpawn.h"
#include "Cpiece.h"
#include "Crook.h"
#include "Cknight.h"
#include "Cbishop.h"
#include "Cking.h"
#include "Cqueen.h"
void main(){
	fstream outfile ("chess1.txt",ios::ate);
	char location[50];
	int confirm=0;
	bool ismovepossible;
	char tocheck;
	int ischeck=0;
	int oldrow=0,oldcolumn=0,newrow=0,newcolumn=0,check =0,end=0;
		int exit=0;
		char chose;
	Cboard myboard;
	
	Cpawn mypawn;
	Crook myrook;
	Cknight myknight;
	Cbishop mybishop;
	Cking myking;
	Cqueen myqueen;


	Cpiece *prook = &myrook;
	Cpiece *ppawn = &mypawn;
	Cpiece *pknight= &myknight;
	Cpiece *pbishop = &mybishop;
	Cpiece *pking = &myking;
	Cpiece *pqueen=&myqueen;
	outfile.open("chess1.txt");
	


	std::cout<<"TO SEE PREVIOS MOVES PRESS Y to PLAY PRESS P ";
	std::cin>>chose;
	
	
	if(chose=='Y'||chose=='y'){
		outfile.open("chess1.txt",ios::beg&&ios::out);//read from beginning 
		
		while(!outfile.eof()){
		 outfile>>oldcolumn;
		 outfile>>oldrow;
		 outfile>>newcolumn;
		 outfile>>newrow;
		(myboard).moveer(&newrow,&newcolumn,&oldrow,&oldcolumn);
		
		(myboard).printboard();
		std::cout<<std::endl;
	    std::cout<<"press any key";
		std::cout<<std::endl;
		std::cin>>tocheck;
}
		
	std::cout<<"all moves done";	


	}
//when entered in here i need to remove the content 	
	if(chose=='P'||chose=='p'){
		outfile.clear(); // clear file
		
		
		
	do{


		std::cout<<std::endl;
		(myboard).printboard();
	
		std::cout<<std::endl;
	std::cout<<"please enter location";
	std::cin>>location;
	check =(myboard).validateuserinput(location,&newcolumn,&newrow,&oldrow,&oldcolumn);
    
	if(check==1){
		
		ismovepossible =false;
	}
	if(check == 0){
		if(ischeck==1){


		  if((myboard).board[oldrow][oldcolumn]->getpiece()=='k'||(myboard).board[oldrow][oldcolumn]->getpiece()=='K'){
			check=0;
			if(myboard.isincheckmate(&oldrow,&oldcolumn,&newrow,&newcolumn,&myboard)==true){
			
			check =0;
			ischeck=0;
			end=0;
			ismovepossible =true;
			}
			else{
				std::cout<<"Checkmate";
				std::cout<<std::endl;
				end=1;
			}
			if(myboard.kingcheck(&oldrow,&oldcolumn,&newrow,&newcolumn,&myboard)==true){
					std::cout<<"Please move to another position";
					std::cout<<std::endl;
					ischeck=1;
					ismovepossible=false;
					check=1;
					}
			
			
		  }
			else{
			check =1;
			ischeck=1;
			ismovepossible =false;
			}
			
	
		
	
	
	}
	}
	if(check==0&&end==0){
		if((myboard).board[oldrow][oldcolumn]->movepiece(&newcolumn, &newrow,&oldrow,&oldcolumn,&myboard)==1){
		
		ismovepossible =true;
		
		}
		else{
			ismovepossible =false;
		}


		
	
	
	}
	if(ismovepossible ==true){
		if (outfile.is_open())
  {
	ios::app;//append  the inputted data to the file
	  outfile<<oldcolumn<<std::endl;
	  outfile<<oldrow<<std::endl;
	  outfile<<newcolumn<<std::endl;
	  outfile<<newrow<<std::endl;
	  }
		else cout << "Unable to open file";
		(myboard).moveer(&newrow,&newcolumn,&oldrow,&oldcolumn);
		(myboard).move();
		
	 if(myboard.incheck(&newrow,&newcolumn,&myboard)==true){
					std::cout<<"King is in check  ";
					ischeck=1;
					}
	}
	outfile.flush();
	}while(end!=1);
	}	
	outfile.close();
}