将向量写入 output 文件 c++

Question

Here I have a structure called contacts

 typedef struct contacts 
    {
       string name;   //{jhonathan , anderson , felicia}
       string nickName; //{jhonny  , andy , felic}
       string phoneNumber; // {13453514 ,148039 , 328490}
       string carrier;  // {atandt , coolmobiles , atandt }
       string address; // {1bcd , gfhs ,jhtd }
    
    } contactDetails;
    
    vector <contactDetails> proContactFile;

I'm trying to write the data inside my vector to a output file.For this i've written the following code

ofstream output_file("temp.csv");
int selectContact;
cout << "Which Contact you want to delete ? Enter the relevent index " << endl;
cin >> selectContact;

if (selectContact > proContactFile.size()) {
    cout << "Invalid entry";
}
else {
    proContactFile.erase(proContactFile.begin() + (selectContact - 1));
    cout << "Delete successfully";
}
  
  ostream_iterator<contactDetails> output_iterator(output_file, "\n");
  copy(begin(proContactFile),end(proContactFile), output_iterator);  
}
output_file.close();
fin.close();
remove("Contact.csv");//Deletes contacts.csv file
rename("temp.csv" , "Contact.csv");

But this code always gives me an error.Also I want to write the data to the file with the following way.

Name,Nick name,Phone number,Carrier,Address

Whats wrong with my code?(basically what i'm doing here is let user to delete a element in the vector and the write that updated vector to a output file)

This is the error I am receiving: Error C2679 binary '<<': no operator found which takes a right-hand operand of type 'const _Ty' (or there is no acceptable conversion)

Answer 1

So using this technique of writing a vector

ostream_iterator<contactDetails> output_iterator(output_file, "\n");
copy(begin(proContactFile),end(proContactFile), output_iterator); 

requires that you overload operator<< for your struct. Ie

ostream& operator<<(ostream& out, const contactDetails& details)
{
    // your output code here, e.g.
    out<< details.name << ',' << details.nickName << ','; //etc << ...
    return out;
}

But the puzzling issue remains. The code above is for updating a file. Which implies that you already have a file. Which implies that you are already successfully writing that file somewhere else in your code. How did you achieve that?

However you managed it you should update that other code so that it uses the operator<< that you are going to write to fix this code. That way all your contact details output goes through one function.