Finding Word + X letters after it - c++

Question

I want to start of by saying that I am still learning and some might think that my code looks bad, but here it goes.
So I have this text file we can call example.txt.
A line in example.txt can look like this:
randomstuffhereitem=1234randomstuffhere
I want my program to take in the numbers that are next to the item= and I have started a bit on it using the following code.
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
string word;
int main()
{
ifstream readFile("example.txt", ios::app);
ofstream outfile("Found_Words.txt", ios::app);
bool found = false;
long int price;
cout << "Insert a number" << endl;
cout << "number:";
cin >> number;
system("cls");
outfile << "Here I start:";
while( readFile >> word )
{
if(word == "item=")
Here is the problem; first of all it only searchs for "item=" but to find it, it cannot be included with other letters. It has to be a standalone word.
It wont find:
helloitem=hello
It will find:
hello item= hello
It has to be separated with spaces which is also a problem.
Secondly I want to find numbers next to the item=. Like I want it to be able to find item=1234 and please note that 1234 can be any number like 6723.
And I dont want it to find what comes after the number, so when the number stops, it wont take in anymore data. Like item=1234hello has to be item=1234
{
cout <<"The word has been found." << endl;
outfile << word << "/" << number;
//outfile.close();
if(word == "item=")
{
outfile << ",";
}
found = true;
}
}
outfile << "finishes here" ;
outfile.close();
if( found = false){
cout <<"Not found" << endl;
}
system ("pause");
}

Answer 1

You can use a code like this:
bool get_price(std::string s, std::string & rest, int & value)
{
int pos = 0; //To track a position inside a string
do //loop through "item" entries in the string
{
pos = s.find("item", pos); //Get an index in the string where "item" is found
if (pos == s.npos) //No "item" in string
break;
pos += 4; //"item" length
while (pos < s.length() && s[pos] == ' ') ++pos; //Skip spaces between "item" and "="
if (pos < s.length() && s[pos] == '=') //Next char is "="
{
++pos; //Move forward one char, the "="
while (pos < s.length() && s[pos] == ' ') ++pos; //Skip spaces between "=" and digits
const char * value_place = s.c_str() + pos; //The number
if (*value_place < '0' || *value_place > '9') continue; //we have no number after =
value = atoi(value_place); //Convert as much digits to a number as possible
while (pos < s.length() && s[pos] >= '0' && s[pos] <= '9') ++pos; //skip number
rest = s.substr(pos); //Return the remainder of the string
return true; //The string matches
}
} while (1);
return false; //We did not find a match
}
Note that you should also change the way you read strings from file. You can either read to newline (std::getline) or to the end of stream, like mentioned here: stackoverflow question