Hi, Im sorta new to c++, so i might need things explaining but what is the best way of reading a txt file, one character at a time and writing each character to a different file??
Hi, Im sorta new to c++, so i might need things explaining but what is the best way of reading a txt file, one character at a time and writing each character to a different file??
Programming is a form of art.
Ok, but how would I do that in a DLL. It comes up saying 'ofstream' undeclared
An ofstream undeclared error probably has nothing to do with it being a DLL. Did you #include <fstream>? Did you specify the std namespace?
it sounds like you havn't included the <fstream> header fileOriginally Posted by Xinco
does it say this at the top of your code >
#include <fstream>
^^ this header is needed for FILE IO ^^
WhAtHA hell Is GoInG ON
Just look at those tutorials.
Code:#include <fstream> using std::ios; int main() { std::fstream dll_rw("my_libs.dll",ios::binary | ios::in | ios::out); if(!dll_rw) { //deal with open failure } else //"else" usually not necessary { //....read and write to DLL file.... dll_rw.close(); //finished -- not necessary, but tidy } return 0; }
"If you tell the truth, you don't have to remember anything"
-Mark Twain
Ok, i found the answer but now its saying 'invalid conversion from 'char' to 'const char''. I thinks its because im using ifstream read_file(argumen0); but I need argument0 to be an argument so how do i fix this
You seem to be reading a character at a time, rather than line at a time. A const char* is a c style string. You should in the else statement, read each line, preferrably into a string (#include <string>), then go on to the next. You should all do this while the file has a next line.
Edit, I see you want to read it a character at a time, since a string can be treated as an array of char, and each char can be referenced with the [] operator, you can read the string, then do a for loop that goes through each char of the string and outputs them.
replace the cout with the output file streamCode:std::string s = "akdnknfknef"; for(std::string::size_type i = 0; i < s.size(); ++i) std::cout << s[i] << std::endl;
Last edited by indigo0086; 01-08-2007 at 10:54 AM.
But I need it to be written 1 character at a time so I can change the ascii value. Sort of like how encryption works (I think) Unless it is possible to change the ascii value of a whole line by a set amount per character.
If you are getting errors it is generally better to post the exact error message and your code so you can get specific help.
As far as reading a character at a time, I would use get() for input, then encrypt the character, then output it. That will move things along one character at a time.
My method;
I think I've got that right. If not, I'll hear about it!Code:int main() { ifstream fin ("your.dll", ios::in | ios:: beg |ios::binary); ofstream out("new.dll, ios::out | ios::binary |ios::app); // verify file open success while(!fin.eof()) { char input = 0; fin.unsetf(ios::skipws); // turn off whitespace skipping fin >> input; //manipulate, encrypt input (1 char) out<<input; //write encrypted byte to output file ("new.dll") } //end while loop //close files return 0; }
Might want to read this. http://faq.cprogramming.com/cgi-bin/...&id=1043284351Code:while(!fin.eof())
dwk
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with my method you can write one char at a time, and manipulate it as such char by char.
Actually, I have. It just continually slips my mind.
Thats an app, I need the code for a programming the DLL. Heres what I got:
DLL.h: (Note, this is header)
DLLmain.cpp: (this is dll c++ code)Code:#ifndef _DLL_H_ #define _DLL_H_ #define export extern "C" __declspec (dllexport) #if BUILDING_DLL # define DLLIMPORT __declspec (dllexport) #else # define DLLIMPORT __declspec (dllimport) #endif class DLLIMPORT DllClass { public: DllClass(); virtual ~DllClass(void); private: }; #endif
I also tried this for the dllmain.cppCode:#include "dll.h" #include <windows.h> #include <fstream> using namespace std; export double func1(char argument0,char argument1) { ifstream readfile; //Here I get the error "invalid conversion from 'char' to 'const char'" ofstream writefile; readfile.open (argument0); writefile.open (argument1); char ch; while (readfile.get(ch)) { writefile << ch; } readfile.close(); writefile.close(); }
Code:#include "dll.h" #include <windows.h> #include <fstream> using namespace std; export double func1(char argument0,char argument1) { ifstream read_file(argument0); //Here I get the error "invalid conversion from 'char' to 'const char'" ofstream write_file(argument1); char ch; while (read_file.get(ch)) { write_file << ch; } read_file.close(); write_file.close(); }
