Question

我用c ++编写了一个代码。我试图在Kdevelop中使用CMake。

我的头文件Newtime.h

class NewTime
{
public:
  NewTime(int = 0, int = 0, int = 0);    //constructor
  void setTime(int, int, int);    // set time
  void dispTime();    //print time
private:
  int hour;
  int minute;
  int second;
};

对于NewTime.cpp我在下面写道：

#include <iostream>
#include <stdio.h>
#include "NewTime.h"
//
NewTime::NewTime(int hr, int min, int sec)  
{
  setTime(hr, min, sec);
}
//
void NewTime::setTime(int h, int m, int s)
{
  hour = ((h >= 0 && h < 24) ? h : 0);
  minute = ((m >= 0 && m < 60) ? m : 0);
  second = ((s >= 0 && s < 60) ? s : 0);
}
//***
void Newtime::dispTime()
{
  std::cout << ((hour == 0 || hour == 12) ? 12 : hour % 12)
       << " : " << (minute < 10 ? "0" : "") << minute
       << " : " << (second < 10 ? "0" : "") << second
       << (hour < 12 ? " AM" : " PM") << std::endl;
}

并且对于主体是：

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <iostream>
#include "NewTime.h"

int main()
{
  NewTime t1, //use default arguments
          t2(2), //only hour defined
          t3(21, 34), //second as default
          t4(12, 25, 42), //everything is defined
          t5(53, 343, 234); //invalid hour
  std::cout << "constructed with: " << std::endl;
  std::cout << "use default arguments: " << std::endl;
  t1.dispTime();
  std::cout << "only hour: " << std::endl;
  t2.dispTime();
  std::cout << "hour and minute: " << std::endl;
  t3.dispTime();
  std::cout << "all defined: " << std::endl;
  t4.dispTime();
  std::cout << "invalid values: " << std::endl;
  t5.dispTime();
  std::cin.get();
  return 0;
}

但我得到了这个错误：

compiling NewTime.cpp (c++)
/home/hasadi/Desktop/tmp/C++/4-6-class-newtimer/newtimer/NewTime.cpp:17: error: ‘Newtime’ has not been declared
/home/hasadi/Desktop/tmp/C++/4-6-class-newtimer/newtimer/NewTime.cpp: In function ‘void dispTime()’:
/home/hasadi/Desktop/tmp/C++/4-6-class-newtimer/newtimer/NewTime.cpp:19: error: ‘hour’ was not declared in this scope
/home/hasadi/Desktop/tmp/C++/4-6-class-newtimer/newtimer/NewTime.cpp:20: error: ‘minute’ was not declared in this scope
/home/hasadi/Desktop/tmp/C++/4-6-class-newtimer/newtimer/NewTime.cpp:21: error: ‘second’ was not declared in this scope

任何想法？我很困惑..

提前感谢您的帮助

Answer 1

你有一个拼写错误，编译器抛出的第一个错误告诉你：

[…]/NewTime.cpp:17: error: ‘Newtime’ has not been declared

您必须将dispTime实现中的Newtime更改为NewTime并且它将构建。现在，编译器不知道dispTime实现与NewTime - 类相关联。

一般情况下，如果在方法实现中获得'varname' was not declared in this scope，则通常是丢失或拼写错误或类/结构类型名称错误。

正如John Zwinck在评论中所说，通常第一个错误是最相关的。您可能只需查看第一个错误就可以自己解决问题。

Answer 2

仔细看看你的拼写！

void Newtime::dispTime()
{
std::cout << ((hour == 0 || hour == 12) ? 12 : hour % 12)
     << " : " << (minute < 10 ? "0" : "") << minute
     << " : " << (second < 10 ? "0" : "") << second
     << (hour < 12 ? " AM" : " PM") << std::endl;
}

你用小写的T拼写它！

错误：未在此范围内声明'小时'

2 个答案: