istring.cpp

来自「C++编程思想所有源码从官方网站上下载包含所需头文件」· C++ 代码 · 共 28 行

//: C04:Istring.cpp
// From "Thinking in C++, Volume 2", by Bruce Eckel & Chuck Allison.
// (c) 1995-2004 MindView, Inc. All Rights Reserved.
// See source code use permissions stated in the file 'License.txt',
// distributed with the code package available at www.MindView.net.
// Input string streams.
#include <cassert>
#include <cmath>  // For fabs()
#include <iostream>
#include <limits> // For epsilon()
#include <sstream>
#include <string>
using namespace std;

int main() {
  istringstream s("47 1.414 This is a test");
  int i;
  double f;
  s >> i >> f; // Whitespace-delimited input
  assert(i == 47);
  double relerr = (fabs(f) - 1.414) / 1.414;
  assert(relerr <= numeric_limits<double>::epsilon());
  string buf2;
  s >> buf2;
  assert(buf2 == "This");
  cout << s.rdbuf(); // " is a test"
} ///:~