在C ++中，seekg似乎包含cr字符，但read（）删除了它们

Question

I'm currently trying to read the contents of a file into a char array.

For instance, I have the following text in a char array. 42 bytes:

{
    type: "Backup",
    name: "BackupJob"
}

This file is created in windows, and I'm using Visual Studio c++, so there is no OS compatibility issues.

However, executing the following code, at the completion of the for loop, I get Index: 39, with no 13 displayed prior to the 10's.

// Create the file stream and open the file for reading
ifstream fs;
fs.open("task.txt", ifstream::in);

int index = 0;
int ch = fs.get();
while (fs.good()) {
    cout << ch << endl;
    ch = fs.get();
    index++;
}

cout << "----------------------------";
cout << "Index: " << index << endl;
return;

However, when attempting to create a char array the length of the file, reading the file size as per below results in the 3 additional CR chars attributing to the total filesize so that length is equal 42, which is adding screwing up the end of the array with dodgy bytes.

// Create the file stream and open the file for reading
ifstream fs;
fs.seekg(0, std::ios::end);
length = fs.tellg();
fs.seekg(0, std::ios::beg);

// Create the buffer to read the file
char* buffer = new char[length];
fs.read(buffer, length);
buffer[length] = '\0';
// Close the stream
fs.close();

Using a hex viewer, I have confirmed that file does indeed contain the CRLF (13 10) bytes in the file.

There seems to be a disparity with getting the end of the file, and what the get() and read() methods actually return.

Could anyone please help with this?

Cheers, Justin

Answer 1

You should open your file in binary mode. This will stop read dropping CR.

fs.open("task.txt", ifstream::in|ifstream::binary);