由于本人要接手一項C++方面 的工作。由于不會C++,不過做過JAVA 以及一些web方面的開發,加之時間比較短。所以需要速成,于是學習筆記也基本都是用代碼代替。
//范例資源文件
/*****************************************************************************************
Test.txt
:
tom 123456789
lilei 234567891
zhangsan 345678912
tom 456789123
xiaohe 567891234????????????????????????????????????????????????????????????????????
******************************************************************************************/
//未用名字空間,使用vector 進行遍歷
/******************************************************************************************
#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <fstream>
int _tmain(int argc,_TCHAR* argv[])
{
std::string strtmp;
std::ifstream fs("Test.txt");
std::vector<std::string> vect;
while(getline(fs,strtmp,'\n'))
{
vect.push_back(strtmp.substr(0,strtmp.find(" ")));
}
for(std::vector<std::string>::size_type index = 0; index < vect.size();index++)
{
std::cout << vect[index]?? << std::endl;
}
return 0;
}
******************************************************************************************/
//使用名字空間,使用vector進行遍歷
/******************************************************************************************
#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <fstream>
using namespace std;
int _tmain(int argc,_TCHAR* argv[])
{
string strtmp;
ifstream fs("Test.txt");
vector<string> vect;
while(getline(fs,strtmp,'\n'))
{
vect.push_back(strtmp.substr(0,strtmp.find(" ")));
}
for(int index = 0; index < vect.size();index++)
{
cout << vect[index]?? << endl;
}
return 0;
}
******************************************************************************************/
//利用迭代器,對vector進行遍歷
/******************************************************************************************
#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <fstream>
using namespace std;
int _tmain(int argc,_TCHAR* argv[])
{
?string strtmp;
?ifstream fs("Test.txt");
?vector<string> vect;
?while(getline(fs,strtmp,'\n'))
?{
??vect.push_back(strtmp.substr(0,strtmp.find(" ")));
?}
?vector<string>::iterator it = vect.begin();
?for(;it != vect.end();it++)
?{
??cout << *it? << endl;
?}
?return 0;
}
******************************************************************************************/
//使用map 進行遍歷
/******************************************************************************************
#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <map>
using namespace std;
int _tmain(int argc,_TCHAR* argv[])
{
?string strtmp;
?ifstream fs("Test.txt");
?map<string,string>? map_temp;
?string::size_type index = string::npos;
?while(getline(fs,strtmp,'\n'))
?{
?index = strtmp.find("");
?map_temp[strtmp.substr(0,index)] = (strtmp.substr(++index));
?}
?map<string,string> ::iterator it = map_temp.begin();
?for(; it != map_temp.end(); it++)
?{
??cout << it->first << " = " << it->second << endl;
?}
?return 0;
}
******************************************************************************************/
//使用for_each 利用重載操作符 進行map遍歷
/******************************************************************************************
#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <map>
#include <iterator>
#include <algorithm>
using namespace std;
class showIiem
{
public:
void operator()(const map<string,string>::value_type& value)
{
cout << value.first << " = " << value.second << "\n";
};
};
int _tmain(int argc,_TCHAR* argv[])
{
?string strtmp;
?ifstream fs("Test.txt");
?map<string,string>? map_temp;
?string::size_type index = string::npos;
?while(getline(fs,strtmp,'\n'))
?{
??index = strtmp.find("");
??map_temp[strtmp.substr(0,index)] = (strtmp.substr(++index));
?}
?showIiem show;
?for_each(map_temp.begin(),map_temp.end(),show);
?return 0;
}
******************************************************************************************/
// 利用copy,使用重載操作符 進行map遍歷
/******************************************************************************************
#include "stdafx.h"
#include <string>
#include <fstream>
#include <iostream>
#include <algorithm>
#include <map>
#include <vector>
using namespace std;
namespace std
{
?std::ostream& operator<<(std::ostream& os, const std::map<std::string,std::string>::value_type& value)
?{
??os << value.first << "= " << value.second;
??return os;
?}
}
class ShowValue
{
public:
?ShowValue(std::ostream& os):m_os(os)
?{
?}
?void operator()(const std::map<std::string,std::string>::value_type& value)
?{
??m_os << value.first << "= " << value.second << "\n";
?}
?std::ostream& m_os;
};
typedef std::ostream_iterator<std::map<std::string,std::string>::value_type> ositertype;
std::ostream& operator<<(std::ostream& os, const std::map<std::string,std::string>& value)
{
?std::for_each(value.begin(), value.end(), ShowValue(os));
?return os;
}
int _tmain(int argc,_TCHAR* argv[])
{
?std::string strtmp;
?std::fstream in("Test.txt");
?std::map<std::string,std::string>? map_1;
?std::string::size_type idx = std::string::npos;
?while(std::getline(in, strtmp, '\n'))
?{
??idx = strtmp.find(' ');
??map_1[strtmp.substr(0, idx)] = strtmp.substr(++idx);
?}
?ositertype os_iter(std::cout, "\n");
?std::copy(map_1.begin(), map_1.end(), os_iter);
?return 0;
}