fig15_22.cpp

来自「是有关C++编程原理教程的例子程序,全,应该对大家有所帮助」· C++ 代码 · 共 54 行

// Fig. 15.22: Fig15_22.cpp 
// Testing error states.
#include <iostream>
using std::cin;
using std::cout;
using std::endl;

int main()
{
   int integerValue;

   // display results of cin functions
   cout << "Before a bad input operation:"
      << "\ncin.rdstate(): " << cin.rdstate()
      << "\n    cin.eof(): " << cin.eof()
      << "\n   cin.fail(): " << cin.fail()
      << "\n    cin.bad(): " << cin.bad()
      << "\n   cin.good(): " << cin.good()
      << "\n\nExpects an integer, but enter a character: ";

   cin >> integerValue; // enter character value
   cout << endl;

   // display results of cin functions after bad input
   cout << "After a bad input operation:"
      << "\ncin.rdstate(): " << cin.rdstate()
      << "\n    cin.eof(): " << cin.eof()
      << "\n   cin.fail(): " << cin.fail()
      << "\n    cin.bad(): " << cin.bad()
      << "\n   cin.good(): " << cin.good() << endl << endl;

   cin.clear(); // clear stream

   // display results of cin functions after clearing cin
   cout << "After cin.clear()" << "\ncin.fail(): " << cin.fail()
      << "\ncin.good(): " << cin.good() << endl;
   return 0;
} // end main

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