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//Download by http://www.NewXing.com /* * This file contains code from "C++ Primer, Fourth Edition", by Stanley B. * Lippman, Jose Lajoie, and Barbara E. Moo, and is covered under the * copyright and warranty notices given in that book: * * "Copyright (c) 2005 by Objectwrite, Inc., Jose Lajoie, and Barbara E. Moo." * * * "The authors and publisher have taken care in the preparation of this book, * but make no expressed or implied warranty of any kind and assume no * responsibility for errors or omissions. No liability is assumed for * incidental or consequential damages in connection with or arising out of the * use of the information or programs contained herein." * * Permission is granted for this code to be used for educational purposes in * association with the book, given proper citation if and when posted or * reproduced.Any commercial use of this code requires the explicit written * permission of the publisher, Addison-Wesley Professional, a division of * Pearson Education, Inc. Send your request for permission, stating clearly * what code you would like to use, and in what specific way, to the following * address: * * Pearson Education, Inc. * Rights and Contracts Department * 75 Arlington Street, Suite 300 * Boston, MA 02216 * Fax: (617) 848-7047 */ #include "io_preamble.h" void f2() { ostringstream format_message; format_message << "val1: " << 512 << "\n" << "val2: " << 1024 << "\n"; istringstream input_istring(format_message.str()); int val1 = 0; int val2 = 0; input_istring >> val1 >> val2; input_istring.clear(); string dump; input_istring >> dump >> val1 >> dump >> val2; cout << val1 << " " << val2 << endl; } int main() { int val1 = 512, val2 = 1024; ostringstream format_message; // ok: converts values to a string representation format_message << "val1: " << val1 << "\n" << "val2: " << val2 << "\n"; cout << format_message.str() << endl; { // str member obtains the string associated with a stringstream istringstream input_istring(format_message.str()); string dump; // place to dump the labels from the formatted message // extracts the stored ascii values, converting back to arithmetic types input_istring >> dump >> val1 >> dump >> val2; cout << val1 << " " << val2 << endl; // prints 512 1024 } f2(); // call f2, which prints val1 and val2 again { istringstream input_istring; // empty istringstream // bind input_istring to string held in format_message input_istring.str(format_message.str()); } return 0; } // Sample code to use getline and istringstream to read a line of text // and then process the line a word at at time void f3() { string line, word; // will hold a line and word from input, respectively while (getline(cin, line)) { // read a line from the input into line // do per-line processing istringstream stream(line); // bind to stream to the line we read while (stream >> word) { // read a word from line // do per-word processing } } }