Deleting specific line from file

Question

These are the contents of my example file:

abcdefg hijk lmnopqrstAB CSTAKLJSKDJD KSA FIND ME akjsdkjhwjkjhasfkajbsdh ADHKJAHSKDJH

I need to find

Answer 1

Try this:

line.replace(line.find(deleteline),deleteline.length(),"");

Answer 2

I'd like to clarify something. Although the answer provided by gmas80 could work, for me, it didn't. I had to modify it somewhat, and here's what I ended up with:

position = line.find(deleteLine);

if (position != string::npos) {
    line.replace(line.find(deleteLine), deleteLine.length(), "");
}

Another thing that didn't satisfy me was that it left blank lines in the code. So I wrote another thing to delete the blank lines:

if (!line.empty()) {
    temp << line << endl;
}

Answer 3

In case anyone would like it I have converted Venraey's useful code into a function:

#include <iostream>
#include <fstream>
    
void eraseFileLine(std::string path, std::string eraseLine) {
    std::string line;
    std::ifstream fin;
    
    fin.open(path);
    // contents of path must be copied to a temp file then
    // renamed back to the path file
    std::ofstream temp;
    temp.open("temp.txt");

    while (getline(fin, line)) {
        // write all lines to temp other than the line marked for erasing
        if (line != eraseLine)
            temp << line << std::endl;
    }

    temp.close();
    fin.close();

    // required conversion for remove and rename functions
    const char * p = path.c_str();
    remove(p);
    rename("temp.txt", p);
}