命名空间定义与异常

Question

我在定义名称空间时遇到了一些麻烦

据我所知，我做对了所有事情

下面是我的代码和构建输出

闪存盘

#ifndef FLASHDRIVE_H
#define FLASHDRIVE_H
#include <iostream>
#include <cstdlib>

namespace cs52 {

class FlashDrive {
    friend FlashDrive operator+ (FlashDrive used1 , FlashDrive used2);
    friend FlashDrive operator- (FlashDrive used3, FlashDrive used4 );

public:

    FlashDrive& FlashDrive::operator=(int);
    FlashDrive::FlashDrive(int);
    FlashDrive& operator = (const FlashDrive& usedtotal){
        my_StorageUsed= usedtotal.my_StorageUsed;
        return *this;
    }
    FlashDrive( );
    FlashDrive( int capacity, int used, bool pluggedIn );

    void plugIn( );
    void pullOut( );
    void writeData( int amount );
    void eraseData( int amount );
    void formatDrive( );

    int  getCapacity( );
    void setCapacity( int amount );
    int  getUsed( );
    void setUsed( int amount );
    bool isPluggedIn( );

private:
    int my_StorageCapacity;   // in kilobytes
    int my_StorageUsed;       // in kilobytes
    bool my_IsPluggedIn;      // am I attached to a computer?
}extern drive1,drive2;

inline FlashDrive operator+ (FlashDrive used1, FlashDrive used2 ) {

    FlashDrive plus;

    plus.my_StorageUsed = (used1.getUsed()+ used2.getUsed());
    return plus;
}
inline bool operator< (FlashDrive &lhs,FlashDrive &rhs ) {
   return ( lhs.getUsed() < rhs.getUsed() );
}
inline bool operator> (FlashDrive &lhs,FlashDrive &rhs ) {
   return ( operator <( rhs, lhs ) );
}
inline FlashDrive operator - (FlashDrive used3, FlashDrive used4 ){
    FlashDrive minus;
    minus.my_StorageUsed = (used3.getUsed()- used4.getUsed());
    return minus;
};

}
#endif 

FlashDrive.cpp

#include <iostream>
#include <cstdlib>
#include "FlashDrive.h"

namespace cs52 {

FlashDrive::FlashDrive( ) {
  my_StorageCapacity = 0;
  my_StorageUsed = 0;
  my_IsPluggedIn = false;
}
FlashDrive::FlashDrive( int capacity, int used, bool pluggedIn ) { 
  my_StorageCapacity = capacity;
  my_StorageUsed = used;
  my_IsPluggedIn = pluggedIn;
}
void FlashDrive::plugIn( ) {
  my_IsPluggedIn = true;
}
void FlashDrive::pullOut( ) {
  my_IsPluggedIn = false;
}
void FlashDrive::writeData( int amount ) {
  my_StorageUsed += amount;
}
void FlashDrive::eraseData( int amount ) {
  my_StorageUsed -= amount;
}
void FlashDrive::formatDrive( ) {
  my_StorageUsed = 0;
}

int  FlashDrive::getCapacity( ) {
  return( my_StorageCapacity );
}
void FlashDrive::setCapacity( int amount ) {
  my_StorageCapacity = amount;
}
int  FlashDrive::getUsed( ) {
  return( my_StorageUsed );
}
void FlashDrive::setUsed( int amount ) {
  my_StorageUsed = amount;
}
bool FlashDrive::isPluggedIn( ) {
  return( my_IsPluggedIn );
}
}

Main.cpp

#include <iostream>
#include <cstdlib>
#include "FlashDrive.h"
void main( )
{
using namespace cs52;
cs52::FlashDrive empty;
cs52::FlashDrive drive1( 10, 0, false );
cs52::FlashDrive drive2( 20, 0, false );

drive1.plugIn( );
drive1.formatDrive( );
drive1.writeData( 5 );
drive1.pullOut( );

drive2.plugIn( );
drive2.formatDrive( );
drive2.writeData( 1 );
drive2.pullOut( );

// read in a FlashDrive... 
// the class designer for FlashDrive (that's you!)
// gets to decide which fields matter and should be read in
cs52::FlashDrive sample;
cin >> sample;

// print out a FlashDrive...
// the class designer for FlashDrive (that's you!)
// gets to decide which fields matter and should be printed
cout << sample << endl;

cs52::FlashDrive combined = drive1 + drive2;
cout << "this drive's filled to " << combined.getUsed( ) << endl;

cs52::FlashDrive other = combined – drive1;
cout << "the other cup's filled to " << other.getUsed( ) << endl;

if (combined > other) {
  cout << "looks like combined is bigger..." << endl;
}
else {
  cout << "looks like other is bigger..." << endl;
}

if (drive2 > other) {
  cout << "looks like drive2 is bigger..." << endl;
}
else {
  cout << "looks like other is bigger..." << endl;
}

if (drive2 < drive1) {
  cout << "looks like drive2 is smaller..." << endl;
}
else {
  cout << "looks like drive1 is smaller..." << endl;
}

// let's throw some exceptions...

try {
  empty = empty - combined;
  cout << "something not right here..." << endl;
} catch( std::logic_error ) {
// an exception should get thrown... 
// so the lines of code here should
// be run, not the cout statement...
}

try {
  drive2.writeData( 10000 );
  cout << "something not right here..." << endl;
} catch( std::logic_error ) {
// an exception should get thrown... 
// so the lines of code here should
// be run, not the cout statement...
}

try {
  cs52::FlashDrive f( -1, -1, false );
  cout << "something not right here..." << endl;
} catch( std::logic_error ) {
// an exception should get thrown... 
// so the lines of code here should
// be run, not the cout statement...
}
}

这是构建错误，其中大多数是多余的

------构建开始：项目：FlashDriver，配置：调试Win32 ------构建开始于2013年7月29日4:32:24 AM。 InitializeBuildStatus：触摸“ Debug \\ FlashDriver.unsuccessfulbuild”。 ClCompile：Main.cpp c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（25）：error C2065：'cin'：未声明的标识符c：\\ documents和settings \\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（30）：错误C2065：'cout'：未声明的标识符c：\\文档和设置\\管理员\\我的文档\\ Visual Studio 2010 \\ Projects \\ FlashDriver \\\\ flashdriver \\ main.cpp（30）：错误C2065：'endl'：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（33）：错误C2065 ：'cout'：未声明的标识符c：\\ documents和settings \\ administrator \\我的文档\\ Visual Studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（33）：错误C2065：'endl'：未声明的标识符c：\\ documents和设置\\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ flashdriver \\ flashdriver \\ main.cpp（35）：错误C2146：语法错误：缺少';' 标识符'–'c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（35）之前：错误C2065：'–'：未声明的标识符c：\\ documents和settings \\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ flashdriver \\ flashdriver \\ main.cpp（35）：错误C2146：语法错误：缺少';' 标识符'drive1'之前c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（36）：error C2065：'cout'：未声明的标识符c：\\ documents和settings \\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（36）：错误C2065：'endl'：未声明的标识符c：\\文档和设置\\管理员\\我的文档\\ Visual Studio 2010 \\ Projects \\ FlashDriver \\ flashdriver \\ main.cpp（39）：错误C2065：'cout'：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（39）：错误C2065 ：'endl'：未声明的标识符c：\\ documents和settings \\ administrator \\我的文档\\ Visual Studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（42）：错误C2065：'cout'：未声明的标识符c：\\ documents和设置\\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（42）：错误C2065：'endl'：未声明的identi 正确的c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（46）：错误C2065：'cout'：未声明的标识符c：\\ documents和settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（46）：错误C2065：“ endl”：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main .cpp（49）：错误C2065：'cout'：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（49）：错误C2065：'endl' ：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（53）：错误C2065：'cout'：未声明的标识符c：\\ documents和settings \\ administrator \\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（53）：错误C2065：“ endl”：未声明的标识符c：\\ documents和 设置\\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（56）：错误C2065：'cout'：未声明的标识符c：\\文档和设置\\管理员\\我的文档\\ Visual Studio 2010 \\ Projects \\\\ flashdriver \\ flashdriver \\ main.cpp（56）：错误C2065：'endl'：未声明的标识符c：\\ documents和settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（62）：错误C2146：语法错误：缺少';' 标识符'–'c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（62）之前：错误C2065：'–'：未声明的标识符c：\\ documents和settings \\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（62）：错误C2146：语法错误：缺少';' 标识符'combined'之前c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（63）：error C2065：'cout'：未声明的标识符c：\\ documents和settings \\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（63）：错误C2065：'endl'：未声明的标识符c：\\文档和设置\\管理员\\我的文档\\ Visual Studio 2010 \\ Projects \\ FlashDriver \\ flashdriver \\ main.cpp（72）：错误C2065：'cout'：未声明的标识符c：\\ documents and settings \\ administrator \\ mydocuments \\ visual studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（72）：错误C2065 ：'endl'：未声明的标识符c：\\ documents and settings \\ administrator \\我的文档\\ Visual Studio 2010 \\ projects \\ flashdriver \\ flashdriver \\ main.cpp（81）：错误C2065：'cout'：未声明的标识符c：\\ documents和设置\\管理员\\我的文档\\ Visual Studio 2010 \\项目\\ FlashDriver \\ FlashDriver \\ Main.cpp（81）：错误C2065：'endl'：未声明的Iden tifier FlashDrive.cpp生成代码...

建立失败。

经过的时间00：00：02.50 ==========构建：0成功，1失败，0最新，跳过0 ==========

Answer 1

cout/cin/endl从STD命名空间，则需要使用std名字空间要符合他们

std::cout
std::cin
std::endl