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c++ - read unknown file


I need help on how to read unknown file format. I can open that file format using Notepad and I can see the content. I tried to read file in way like we read text file but I cannot.

Please let me know how can I read unknown files which I can open with Notepad.

1 Solution
Perhaps you need to open the file in binary mode. Can you show us the screenshot of how the file looks like in Notepad?
BTW, you have specified the following tags and topics:
Tags: c++, visual studio, eclipse
Topics: C++ Programming Language, Microsoft Visual C++.Net

What exactly is your language of choice? Is it pure C++, MFC or C++/CLI (i.e. .Net)?
josephm67Author Commented:
In Notepad, file show correct text like "This is line 1", This is line 2. The real english characters.

Any help please..
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josephm67Author Commented:
I am using Visual Studio for C++ but I am trying to use pure C++.
Hi josephm67,

could you post the code you wrote so far? And it would be great if you could post a sample file here too.

Best regards,

different software programs encode characters in different ways. notepad can manage text encoded in several formats such as ANSI, Unicode (UTF-16) and UTF-8. find these options by clicking the "Encoding" button on notepad's 'Save As' window.

if it is ansi, you would open and read it in c++ as text like

std::string strfile = "c:\\temp\\myfile.xyz";
std::ifstream ifs(strfile.c_str());
std::string line;
while (std::getline(ifs, line))
    // do something with text line

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if UTF-16, each character has two bytes and you would read it accordingly.

you would then use std::wstring instead of std::string and std::wifstream indtead of std::ifstream. literals like "c:\\temp\\file" would get preceeded by an L.

if UTF-8 it is a single-byte encoding like with ANSI. so you would use the code above but then have to convert from UTF-8 to ANSI or UTF-8 to UTF-16 if the line contains UTF-8 characters which use multiple bytes for all codes above ascii 7-bit. code to convert from UTF-8 to wide strings is like

const std::locale empty_locale = std::locale::empty();
typedef std::codecvt_utf8<wchar_t> converter_type;
const converter_type* converter = new converter_type;
const std::locale utf8_locale = std::locale(empty_locale, converter);
std::wifstream stream(L"test.txt");
std::wstring line;
std::getline(stream, line);

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josephm67Author Commented:
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