Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
384 views
in Technique[技术] by (71.8m points)

c++ - How to read a specific amount of characters from a text file

I tried to do it like this

 #include <iostream>
 #include <fstream>

using namespace std;

int main()
{
    char b[2];
    ifstream f("prad.txt");
    f>>b ;
    cout <<b;
    return 0;
}

It should read 2 characters but it reads whole line. This worked on another language but doesn't work in C++ for some reason.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

You can use read() to specify the number of characters to read:

char b[3] = "";
ifstream f("prad.txt");

f.read(b, sizeof(b) - 1); // Read one less that sizeof(b) to ensure null
cout << b;                // terminated for use with cout.

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...