Reading a whole Text file.

Hello, i have made an encryption program, but im wondering how to read a whole text file and save it to a char.

I'm using eof to actually read until the end of the file.

But, it doesn't actually save the whole file to the char.

So actually, it will only read one line, and not the whole file.

I hope you can help me, thank you.

If your text file is longer than one character long, then of course it won't fit in a char.

Anyway, is there a reason you need the whole file at once? (It's not unheard of to process N characters at a time, for some reasonably large N.) If so, then you'll have to figure out how large the file is, make sure you have enough memory space somewhere, and then read into that memory.

Save it to a char? Theres no way you could save a whole text file to a single character.

I know, hehe, i actually need to read the whole file to encrypt the whole file.

All im encrypting is 1 line.

Not in 1 char. In a char array. I'm actually saving a complete line. But i just need the code to read a whole file.


I'm not really familiar with Fstream.

You can check my other topic: Ageofempire text game. I'm actually not a begginer in c++. It's just fstream. I'm still learning it.

Originally Posted by kevinawad

I know, hehe, i actually need to read the whole file to encrypt the whole file.

All im encrypting is 1 line.

Not in 1 char. In a char array. I'm actually saving a complete line. But i just need the code to read a whole file.


I'm not really familiar with Fstream.

You can check my other topic: Ageofempire text game. I'm actually not a begginer in c++. It's just fstream. I'm still learning it.

If you have a char array, then you can only save N-1 characters, where N is the size of the array that you declared.

Maybe I wasn't clear with my statement: if you're only encrypting one line, why do you care about the rest of the file? (I mean, why do you need to keep it around? Why not just write it to the new file right away and be done with it?)

But again, if you need the whole file, then you need to first find out how large the file is, so that you can create enough chars to hold it all.

Don't worry about the char...

I'm just asking how to read a whole file , that's all.

Thank you, and i hope you can help me.

Originally Posted by kevinawad

Don't worry about the char...

I'm just asking how to read a whole file , that's all.

Thank you, and i hope you can help me.

But ... your first post says you know how to read a whole file. If for some reason you don't, it looks like this:

Code:

while (inFile >> foo);

assuming you're willing to go word by word. If you wanted to go lines at a time, you could use getline instead.

char str[5000];

while(PhpFile >> str);

Doesnt work.

Even if i write

while(PhpFile >> str[5000]); it will print many chars.

Of course it works. As mentioned it will read one word at a time.

If you want more specific help, maybe you should ask a specific question.

Nevermind, i found out how...

Code:

 
string All;
 
while(!PhpFile.eof())
{
PhpFile.getline(str, 5000);
All = All + str;
}

Then, str will be == to All.

So actually, it will save to a string, then resave to a char. Thank you.

Originally Posted by kevinawad

So actually, it will save to a string, then resave to a char.
[/SIZE]

As long as you're aware that this sentence is not in any way true, then we're fine.

Originally Posted by kevinawad

Nevermind, i found out how...

Code:

 
string All;
 
while(!PhpFile.eof())
{
PhpFile.getline(str, 5000);
All = All + str;
}

Then, str will be == to All.

So actually, it will save to a string, then resave to a char. Thank you.

Yeah, what tabstop says about your last two lines there.

Also, don't use eof() like you are for testing before a read. Just put the getline call into your while loop condition. eof() is used after a read fails to help determine what caused the failure.

Lastly, you are throwing away newlines. getline() omits them. You will have to put those back in when you append the line to All.

However, you can avoid all of this crap and fuss by just reading straight into the string with istream_iterator. You won't even need the character array or any loops to do it.

Code:

#include <iomanip>     // for noskipws, to keep whitespace and newlines
#include <iterator>    // for istream_iterator
...
PhpFile >> noskipws;     
string All(istream_iterator<char>(PhpFile), istream_iterator<char>());

(not tested)...and that should slurp the whole file into the string All. Hocus Pocus!