How do i find a string in a file? In my code, i want to find the name of a person in the file. and do the actions in the comments. Here is my code:
int main(){
size_t found;
ofstream myfile;
cout << "Enter the name you wish to delete." << endl;
getline(cin, name);
myfile.open("database.dat");
found=myfile.find(name);
if (found!=string::npos){
number = myfile.tellg();
/*Delete current line and next line*/
}
}
Do you want to modify the file, or simply skip those two lines while reading?
Actually, the solution is the same for both, because removing data from the middle of the file requires reading everything after that and rewriting it with an offset (just like removing an element from the middle of an array).
So, read the entire file into memory except for any lines you determine need to be deleted (just skip those). After that, write the surviving lines back to disk. It’s probably a good idea to use a temporary file which gets moved to the original name as a final step, so that data isn’t destroyed if your process is aborted.