Question

这是一个library.h的片段顺便说一下这是一个library.h的片段。

 #include <windows.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
 #include <vector>
 #include <string>
 #include <iostream>
 #include <fstream>
 #pragma warning (disable:4267)
 #pragma warning (disable:4311)
 #pragma warning (disable:4313)
 #pragma warning (disable:4244)
 #pragma warning (disable:4996)
 #pragma warning (disable:4800)
 #pragma warning (disable:4018)
 #pragma comment( lib, "library.lib" )
 using namespace std;

Library.h是一个头文件，它是一个图形库，也包含已经包含的大部分C ++库，我需要打印来自database1.txt的所有值，顺便说一下，如果我的代码看起来像灾难没有编码C ++已经四年了。

#include <library.h>
#include <iterator>
#include <vector>
#include <sstream>

struct st {
double month;
double day;
double year;
double social;
string fname;
string lname; 
double address;
}roll [14];
void rawr (st dat);

void main()
{
ifstream meow("database1.txt");

{
if (meow.fail())
cout << "Not enough data in the file!, NOOB";
}
int n;
while (meow){
double d;
string e, f;
double  g;
double a, x, c;
meow>>a;
meow>>x;
meow>>c;
meow>> d;
meow>> e;
meow>> f;
meow>>g;
cout << a<<" "<<x<<" "<< c<< " "<<d<<" "<<e<<" "<<f<<" "<<g;
for (n=0; n<14; n++)
{
stringstream(a)>> roll[n].month;
stringstream(x)>> roll[n].day;
stringstream(c)>> roll[n].year;
stringstream(d)>> roll[n].social;
stringstream(e)>> roll[n].fname;
stringstream(f)>> roll[n].lname;
stringstream(g)>> roll[n].address;  
}
for (n=0; n<14; n++)
rawr (roll[n]);
} 
}
void rawr (st dat)
{
    cout << dat.month<<" "<<dat.day<<" "<< dat.year<< " "<<dat.social<<" "<<dat.fname<<" "<<dat.lname<<" "<<dat.address;
}

Answer 1

我认为你应该在担心库标题之前让你的简单程序工作。你的程序有太多问题。让我们更喜欢更简单的方法：

struct Record
{
  unsigned int  month;  // Month's can't be negative nor floating point.
  unsigned int  day;
  unsigned int  year;
  std::string   social;  // Social has form xxx-xx-xxxx, so it can't be floating point.
  std::string   first_name;
  std::string   last_name;
  std::string   address;
};

要更轻松地从流中输入，请过载operator >>：

struct Record
{
  // Same as above
  friend std::istream& operator>>(std::istream& input, Record& r);
};

std::istream& operator>>(std::istream& input, Record& r)
{
  input >> r.month;
  input >> r.day;
  input >> r.year;
  input >> r.social;
  input >> r.first_name;
  input >> r.last_name;
  input >> r.address;
  return input;
}

重载operator>>会使输入变得更加容易：

int main(void)
{
  std::ifstream database_stream("database1.txt");
  if (!database_stream)
  {
    std::cerr << "Error opening database1.txt\n";
    return EXIT_FAILURE;
  }
  //  This code will be execute if the file was opened successfully.
  std::vector<Record> database;
  Record r;
  while (database_stream >> r)
  {
    database.push_back(r);
  }
  return EXIT_SUCCESS;
}

无需stringstream。 Record的输入功能已封装到Record对象中，从而简化了main功能。

operator<<也可以在Record结构中以类似的方式重载main。这也将简化month功能。

编辑1：重构
day，year和into a separate可以是*重构struct Date { unsigned int month; unsigned int day; unsigned int year; friend std::istream& operator>>(std::istream& input, Date& d); friend std::ostream& operator>>(std::ostream& output, const Date& d); }; std::istream& operator>>(std::istream& input, Date& d) { input >> d.month >> d.day >> d.year; return input; } std::ostream& operator<<(std::ostream& output, const Date& d) { output << d.month << "\t" << d.day << "\t" << d.year; return output; } Date`类（可以在其他作业中重复使用）：

Record

您的struct Record { Date d; std::string social; // Social has form xxx-xx-xxxx, so it can't be floating point. std::string first_name; std::string last_name; std::string address; friend std::istream& operator>>(std::istream& input, Record& r);然后简化为：

Record::operator>>

};

您的std::istream& operator>>(std::istream& input, Record& r) { input >> r.d >> r.social >> r.first_name >> r.last_name >> r.address; return input; }方法简化为：

Date

如果将Date.cpp结构放入单独的文件中，则可以通过将头文件包含到其他源文件中来重复使用它，然后将 <div ng-repeat = "item in data"> <div ng-repeat = "sub-item in item"> <div id = "{{$index}}"> </div> </div>文件添加到项目中。无需浪费时间重写或测试它。： - ）

为什么这不会打印txt文件中的值

1 个答案: