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Solved

Readfile Question...

Posted on 2004-04-12
5
Medium Priority
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Last Modified: 2010-04-01
I am trying to read a file into a string and crypt it, I don't want to use getline (since some of file does not have any specific character such as '\n'), read by char and crypt it is too slow, so I would like read amount of characters into a string, and then just crypt it.
I select 3000 character each time I read from file, my code like below...
CAN SOMEONE TEACH ME MORE EFFICIENT WAY TO DO THIS JOB???

THANK YOU SO MUCH....

//======================================================
// The code is work, but I would like to know if any efficient way to do this job... Thanks
//======================================================
const int AMOUNT = 3000;
......
ifstream ifile;
string filename = "c:\\test.txt";
ifile.open(filename.c_str());
if(!ifile.is_open())
    return;

string str = "";
char c;
while(!ifile.eof())
{
   str = "";
   for(int i = 0; i < AMOUNT && !ifile.eof(); i++)
   {
       ifile >> c;
       str += c;
   }
   doCrypt(str);
}
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Question by:billcch
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5 Comments
 
LVL 44

Accepted Solution

by:
Karl Heinz Kremer earned 2000 total points
ID: 10806439
Use ifstream::read(char *buffer, int size), so in your case this would be

char buffer[AMOUNT];
ifile.read(buffer, AMOUNT);

BTW: This is usually done with a "Points for ..." question, not a completely new question. See the EE Help for more information (http://www.experts-exchange.com/Programming/Programming_Languages/Cplusplus/help.jsp#hi50).
0
 

Author Comment

by:billcch
ID: 10806463
Thank you khkremer....
0
 
LVL 44

Expert Comment

by:Karl Heinz Kremer
ID: 10806556
On second thought, you should probably delete this question (have it deleted by the Support team) and reopen the first question (support can also do this for you).
0
 

Author Comment

by:billcch
ID: 10806595
hi, khkremer:
is this your email address?
eexchange@khk.net
Thanks!
billcch
0
 

Author Comment

by:billcch
ID: 10807782
Again, Thank you very much khkremer....
Billcch
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