将文件中的所有行存储到字符串数组

Question

I have following code to read a text file line by line and store data in a string* variable:

#include <string>
#include <fstream>
#include <iostream>
using namespace std;

int main(){
    // open a file in read mode.
   ifstream infile; 
   infile.open("iris.csv"); 

    // read file line by line and store here: 
    string *strlist; 
    int count =0; 
    for (string line; getline(infile, line); ) {
        strlist[count] = line; 
        count++; 
    }
    infile.close(); 
    //print all lines: 
    for (int i=0; i<count; i++){
        cout << strlist[i];
    }
}

Will above work or will there be some memory problem. Do I need to make a new string before assigning a value strlist[i]=line ?

I did not try it fearing that an error may cause data damage. Thanks for your help.

Answer 1

Using vector is a good option.

#include <string>
#include <vector>
#include <fstream>
#include <iostream>
using namespace std;

int main(){
    // open a file in read mode.
   ifstream infile; 
   infile.open("iris.csv"); 

    // read file line by line and store here: 
    vector<string> strlist; 

    for (string line; getline(infile, line); ) {
    //or
    //while (getline(infile, line)) {
        strlist.push_back(line); 
    }
    infile.close(); 
    //print all lines: 
    for (int i=0; i<strlist.size(); i++){
        cout << strlist[i];
    }
}

Answer 2

I think if you want to load the file all in one time in c++, it must will crush your memory. just read one line and do something on it or make a counter to remember how much you had loaded.After you finish one part then go for next one.