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Well...what is different? Missing line-breaks? In this case...Quote:
Originally Posted by scootz3345
should help...Code:while(std::getline(in, t))
out << t << std::endl;
Besides that...if you simply want to copy a file there are easier methods... ;
thanx man...actually this is just a part of a program...:)
i am finding how to change the content of the opened file n come out with the output in a new file...
thanx for the help
whats the different between struct, pointer and array???
lets if i have words, name:my name is eric stored in a file a.txt
how can it be detected so that " my name is eric " can be stored in a variable "name" ??
can anyone help me???
The variable name has to be there during compiling, thus cannot be applied dynamically at run-time...other than that you simply parse your file...
Code:#include <string>
#include <fstream>
#include <iostream>
int main()
{
// Open file
std::ifstream in("c:\\test.txt");
if(!in)
return -1; // Could not open file
// Read line-by-line
std::string t;
std::string name;
while(std::getline(in, t))
{
std::string::size_type pos = t.find("name:");
if(pos != std::string::npos)
name = t.substr(pos + 1);
}
// Close file
in.close();
std::cout << name << std::endl;
return 0;
}
thanx again for the code!
the code is compiled and run successfully, however it didn't produce any output...can u help me find whats wrong with it ??
really appreciate it!
Well...I would simply assume that there is no "name:" string in the file...can you upload the file here?
ok..thanx..i'll upload the file..
actually im just using the variable "name" as an example.
This is a sample of a syslog file.
Actually what im trying to do is, if u see in the example.txt, there is a word
"date=2005-04-26". I want the code to detect "date=" and return the
value of "2005-04-26" into a variable so that it can be sent to the
database field. And then also return other values such as "device_id"
and "log_id".
Thanx so much !!
Well...I don't see "date=" or anything else you mentioend in the file...however, you simply need to exchange the 'name:" in the 'find()' function to the appropriate search value you want...e.g. "date=".
Same goes for extracting the data....if they are in the middle of the line you need to calculate both the beginning (by using 'find()') and the end (by using 'find()' again for example)...
sorry..my bad...i have posted a wrong file...
this is the correct file..
can u write me an example using find() from this file??
I have managed to open the file n separate the content, however i have this problem where
display_string(buffer, "date=", 'a');
:
:
:
void display_string( char *buff, char *str, char flag )
{
char *plocation;
int pos=0;
char *tmp = buff;
char d[100];
char ff = flag;
int j=0;
int len = strlen(str);
switch(ff)
{
case 'a':
len=len+10;
break;
case 'b':
len=len+8;
break;
as u can see im reading it by counting the line after each word in case example "date=" ---len+10..10 character after the word "date=" will be consider as date..
however i have problems..what if we set it as 14..the date only contain of 10 so it will also display the balance of other 4 character..
it will display them as well..example "12-10-2005 sed" 14 character
how can i make it so that it will not take any other character after the space???
plocation = strstr( tmp, str);
pos = plocation - tmp;
if (plocation)
{ cout<<"\n\t";
//cout<<"\nThe time of this entry is:"<<endl;
for(int i=pos;i<pos+len;i++)
{
//do{
d[j]=buff[i];
//cout<<buff[i];
//}while (d[j]!=[ ]);
cout<<d[j];
j++;
}
//cout <<pos<<endl;
}
Change the following part of my previous code
Not tested though....Code:// Read line-by-line
std::string t;
std::string pattern("date=");
std::string date;
// Get one line
while(std::getline(in, t))
{
// Find the beginning position in the string of the following pattern
std::string::size_type pos = t.find(pattern);
// Check whether we reached the end of the string (-> pattern not found)
if(pos != std::string::npos)
{
// Extract the value of the pattern. The value starts at the returned
// position plus the length of the pattern and ends at the next space.
// Thus, we need to find the next space beginning at pattern position.
// The returned position then needs to be recalculated so that we get
// the number of characters we want to extract. Thus, we subtract
// the beginning position plus the length of the pattern from the
// position of the space...
data = t.substr(pos + pattern.length() , t.find(" ", pos) - pos + pattern.length());
}
}
there's 1 error:
this is the whole codes:
#include <string>
#include <fstream>
#include <iostream>
int main()
{
char data;
char name;
// Open file
std::ifstream in("samplesyslog.txt");
if(!in)
return -1; // Could not open file
// Read line-by-line
std::string t;
std::string pattern("date=");
std::string date;
while(std::getline(in, t))
{
std::string::size_type pos = t.find(pattern);
if(pos != std::string::npos)
{
data = t.substr(pos + pattern.length() , t.find(" ", pos) - pos + pattern.length());
}
}
// Close file
in.close();
std::cout << date << std::endl;
return 0;
}
This is the error:
C:\Documents and Settings\Administrator\My Documents\3 June 2005\adreas maseur\sample5.cpp(23) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class
std::allocator<char> >' (or there is no acceptable conversion)
Error executing cl.exe.
sample5.obj - 1 error(s), 0 warning(s)
Please test it for me...thanx
It should be
Code:date = t.substr(pos + pattern.length() , t.find(" ", pos) - pos + pattern.length());
I think this should be nominated for the Question Of The Month awardQuote:
Originally Posted by scootz3345
thanx andreas, u help me alot.
however, the output takes the value of date and also the next string..
example, output: 2005-04-26 time:18:3
and please if can u explain a bit how the code works so that i can expand it for other variables.
thanx!