I want to read out the chrome history from its file. I want to get all characters and null byte that's in that file. The problem I'm facing is that I only get some part of the text that's in the file. I belive it stop due to a null byte or a speical character.
Here´s my code that I have at the moment.
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
using namespace std;
int main(){
string str;
std::ifstream in("c:/Users/Petrus/Documents/History"); // I have copy my file into my documents to make sure I'm not interfering with Chrome.
std::stringstream buffer;
if (!in.is_open()){
cout << "Failed to open" << endl;
}
else{
cout << "Opened OK" << endl;
}
buffer << in.rdbuf();
std::string contents(buffer.str());
while (getline(buffer, str))
{
cout << str;
}
in.close();
system("PAUSE");
return 0;
}
If you want to take a look at the chrome history file its located at:
C:\Users\YOUR NAME\AppData\Local\Google\Chrome\User Data\Default -->History
(PS You have to include hidden files to be able to see Appdata.)
Thanks in advance
std::getline() should be used only to read plain text files.
To read arbitrary binary files you should use read(). Additionally, on your operating system you must open binary files using the std::ios::binary flag.
Related
I'm trying to read a text file and output the contents. It's just I can't seem to find the right method and the ones I've used (including this one), seems to wipe the text file. The code:
std::string Line;
std::ifstream File("Account.txt");
if (File.is_open()) {
while (getline(File, Line)) {
std::cout << Line << std::endl;
}
}
else {
std::cout << "Unable to open File" << std::endl;
}
File.close();
I'm also using:
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
I'm using this code (below) every time the program runs to create the file which might be the error, if so can anyone recommend a way to create the file only if it doesn't already exist
std::ofstream File("Account.txt");
File.close();
Your file is being wiped by your file creating code.
std::ofstream File("Account.txt");
File.close();
To create a file without wiping existing contents try this
std::ofstream File("Account.txt", std::ios_base::app);
File.close();
I have some code here
https://github.com/Fallauthy/Projects/blob/master/cPlusPlusProjects/bazaPracownikow/bazaPracownikow/bazaPracownikow/main.cpp
And I have no idea how to show contents in my file. I mean i know how, but it doesn't show same I Have in file (in link). It show in next line. This code is responsible to load file
while (!baseFile.eof()) {
//wczytaj zawartosc pliku do zmiennej
std::string buffer;
baseFile >> buffer;
//wypisz
loadLineFromBase += buffer;
loadLineFromBase += " \n";
}
std::cout << loadLineFromBase << std::endl;
Unless I see all your code all I can do for you is give you a sample in return, I don't know what you're trying to do but it seems in this case you're looking for this.
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main()
{
string Display = "";
ofstream FileOut;
ifstream FileInput;
FileOut.open("C:\\Example.txt");
FileOut << "This is some example text that will be written to the file!";
FileOut.close();
FileInput.open("C:\\Example.txt");
if (!FileInput)
{
cout << "Error File not Found: " << endl;
return 1;
}
while (!FileInput.eof())
{
getline(FileInput, Display);
}
FileInput.close();
cout << Display << endl;
return 0;
}
Simply put if you're currently working wit ha text document
use getline()
When you use getline() it takes two arguments the first will be in this case your ifstream object, as in what you're using to open the file. The second will be the string you're using to store the contents in.
Using the method I outlined above you'll be able to read the entire file contents.
And please next time as it was said above outline your problem more in depth and if you provide us with all of your code we may better assist you!
Your snippet of code automatically add a newline to every string read from the input file, even if originally those were words separeted by spaces. Probably you want to keep the structure of the original file, so it's better to read one line at a time and, unless you need it for some other uses, print it out in the same loop.
std::string buffer;
// read every line of baseFile till EOF
while ( std::getline(baseFile, buffer) ) {
std::cout << buffer << '\n';
}
#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <process.h>
using namespace std;
int main(){
system("cls");
char mline[75];
int lc=0;
ofstream fout("out.txt",ios::out);
ifstream fin("data.txt",ios::in);
if(!fin){
cerr<<"Failed to open file !";
exit(1);
}
while(1){
fin.getline(mline,75,'.');
if(fin.eof()){break;}
lc++;
fout<<lc<<". "<<mline<<"\n";
}
fin.close();
fout.close();
cout<<"Output "<<lc<<" records"<<endl;
return 0;
}
The above code is supposed to read from the file "data.txt" the following text
"The default behaviour of ifstream type stream (upon opening files ) allows users
to read contents from the file. if the file mode is ios::in only then reading is
performed on a text file and if the file mode also includes ios::binary along with
ios::in then, reading is performed in binary mode. No transformation of characters
takes place in binary mode whereas specific transformations take place in text mode."
and create a file out.txt , in which the same text is stored using line numbers ( A line can have 75 characters or ends at '.' - whichever occurs earlier ).
Whenever I run the program, it just gets stuck at the console - which doesnt respond upon pressing any keys whatsoever.
Can someone tell me what's going on in here ?
If any one of the attempted reads in the file is longer than 74 characters, getline will set the failbit for fin, and you will never reach the end of the file. Change your code to the following:
for (; fin; ++lc) {
fin.getline(mline,75,'.');
if (!fin.eof() && !fin.bad())
fin.clear();
fout<<lc<<". "<<mline<<"\n";
}
This will break your loop if you reach the end of the file or if something catastrophic happens to the stream. You'll also need to think about handling the extra read that is performed if the file ends with a period.
Consider switching to std::string.
#include <iostream>
#include <fstream>
#include <string>
int main()
{
int lc = 0;
std::ofstream fout("out.txt");
std::ifstream fin("data.txt");
for (std::string line; getline(fin, line, '.'); )
fout << ++lc << ". " << line << "\n";
std::cout << "Output " << lc << " records\n";
}
I currently have this code, but I would like to be able to output to a .csv file, rather than just print to screen. Does anyone know how to do this?
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
string Weather_test;
int main()
{
ifstream Weather_test_input;
Weather_test_input.open("/Users/MyName/Desktop/Weather_test.csv");
getline(Weather_test_input, Weather_test, '?');
Weather_test.erase(remove_if(Weather_test.begin(), Weather_test.end(), ::isalpha), Weather_test.end());
cout << Weather_test;
return 0;
}
If the Weather_test string is formatted properly.
ofstream Weather_test_output("path_goes_here.csv", ios::app);
// this does the open for you, appending data to an existing file
Weather_test_output << Weather_test << std::endl;
Weather_test_output.close();
If it is not formatted properly then you need to separate it into "fields" and write them with commas between them. That's a separate question.
Writing a string to a CSV file is like writing a string to any file:
std::string text = "description"
output_file << description << ", " << 5 << "\n";
In your example, you can't write to an ifstream. You can write to ofstream and fstream but not ifstream.
So either open the file for reading and writing or close after reading and open as writing.
To write to csv is to create an ostream and open file named "*.csv". You can use operator<< on this object in the same way as you have used it previously to write to the standard output, std::cout:
std::ofstream f;
f.open( "file.csv", std::ios::out);
if ( !f) return -1;
f << Weather_test;
f.close();
Thanks people you here are all truly amazing!
I managed to get my final piece of code which (removes all letters of the alphabet from my .csv file). Here it is for posterity
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
string Weather_test;
int main()
{
ifstream Weather_test_input;
Weather_test_input.open("/Users/MyName/Desktop/Weather_test.csv");
getline(Weather_test_input, Weather_test, '?');
Weather_test.erase(remove_if(Weather_test.begin(), Weather_test.end(), ::isalpha), Weather_test.end());
ofstream Weather_test_output("/Users/MyName/Desktop/Weather_test_output.csv", ios::app);
Weather_test_output << Weather_test << std::endl;
Weather_test_output.close();
cout << Weather_test;
return 0;
}
Thanks again all!
I'd like to be able to add lines to the beginning of a file.
This program I am writing will take information from a user, and prep it to write to a file. That file, then, will be a diff that was already generated, and what is being added to the beginning is descriptors and tags that make it compatible with Debian's DEP3 Patch tagging system.
This needs to be cross-platform, so it needs to work in GNU C++ (Linux) and Microsoft C++ (and whatever Mac comes with)
(Related Threads elsewhere: http://ubuntuforums.org/showthread.php?t=2006605)
See trent.josephsen's answer:
You can't insert data at the start of a file on disk. You need to read the entire file into memory, insert data at the beginning, and write the entire thing back to disk. (This isn't the only way, but given the file isn't too large, it's probably the best.)
You can achieve such by using std::ifstream for the input file and std::ofstream for the output file. Afterwards you can use std::remove and std::rename to replace your old file:
#include <iostream>
#include <fstream>
#include <string>
#include <cstdio>
int main(){
std::ofstream outputFile("outputFileName");
std::ifstream inputFile("inputFileName");
outputFile << "Write your lines...\n";
outputFile << "just as you would do to std::cout ...\n";
outputFile << inputFile.rdbuf();
inputFile.close();
outputFile.close();
std::remove("inputFileName");
std::rename("outputFileName","inputFileName");
return 0;
}
Another approach which doesn't use remove or rename uses a std::stringstream:
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
int main(){
const std::string fileName = "outputFileName";
std::fstream processedFile(fileName.c_str());
std::stringstream fileData;
fileData << "First line\n";
fileData << "second line\n";
fileData << processedFile.rdbuf();
processedFile.close();
processedFile.open(fileName.c_str(), std::fstream::out | std::fstream::trunc);
processedFile << fileData.rdbuf();
return 0;
}