C++ 使用模板(template) 扩展std::string

2019-11-08 20:22:22

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C++ 使用模板(template) 扩展std::string

Github: https://github.com/LowBoyTeam/string_helper

string_helper.hpp

/** Author: LowBoyTeam (https://github.com/LowBoyTeam)* License: Code PRoject Open License* Disclaimer: The software is provided "as-is". No claim of suitability, guarantee, or any warranty whatsoever is provided.* Copyright (c) 2016-2017.*/#ifndef _STRING_HELPER_HPP_INCLUDED_#define _STRING_HELPER_HPP_INCLUDED_#include <stdarg.h>#include <string>#include <vector>#include <sstream>#include <fstream>#include <algorithm>#include <iomanip>namespace string_helper{ inline std::string format(const char *fmt, ...) { std::string strResult = ""; if (NULL != fmt) { va_list marker = NULL; va_start(marker, fmt); size_t nLength = _vscprintf(fmt, marker) + 1; std::vector<char> vBuffer(nLength, '/0'); int nRet = _vsnprintf_s(&vBuffer[0], vBuffer.size(), nLength, fmt, marker); if (nRet > 0) { strResult = &vBuffer[0]; } va_end(marker); } return strResult; } inline std::wstring format(const wchar_t *fmt, ...) { std::wstring strResult = L""; if (NULL != fmt) { va_list marker = NULL; va_start(marker, fmt); size_t nLength = _vscwprintf(fmt, marker) + 1; std::vector<wchar_t> vBuffer(nLength, L'/0'); int nWritten = _vsnwprintf_s(&vBuffer[0], vBuffer.size(), nLength, fmt, marker); if (nWritten > 0) { strResult = &vBuffer[0]; } va_end(marker); } return strResult; } template <class T> inline std::vector<std::basic_string<T>> compact(const std::vector<std::basic_string<T>> &tokens) { std::vector<std::basic_string<T>> compacted; for (size_t i = 0; i < tokens.size(); ++i) { if (!tokens[i].empty()) { compacted.push_back(tokens[i]); } } return compacted; } template <class T> inline std::vector<std::basic_string<T>> split(const std::basic_string<T>& str, const std::basic_string<T>& delim, const bool trim_empty = false) { size_t pos, last_pos = 0, len; std::vector<std::basic_string<T>> tokens; while (true) { pos = str.find(delim, last_pos); if (pos == std::wstring::npos) { pos = str.size(); } len = pos - last_pos; if (!trim_empty || len != 0) { tokens.push_back(str.substr(last_pos, len)); } if (pos == str.size()) { break; } else { last_pos = pos + delim.size(); } } return tokens; } template <class T> inline std::basic_string<T> join(const std::vector<std::basic_string<T>> &tokens,const std::basic_string<T>& delim, const bool trim_empty = false) { if (trim_empty) { return join(compact(tokens), delim, false); } else { std::basic_stringstream<T> ss; for (size_t i = 0; i < tokens.size() - 1; ++i) { ss << tokens[i] << delim; } ss << tokens[tokens.size() - 1]; return ss.str(); } } template <class T> inline std::basic_string<T> trim(const std::basic_string<T>& str) { if (str.empty()) { return str; } std::basic_string<T> sstr(str); std::basic_string<T>::iterator c; // Erase whitespace before the string for (c = sstr.begin(); c != sstr.end() && iswspace(*c++);); sstr.erase(sstr.begin(), --c); // Erase whitespace after the string for (c = sstr.end(); c != sstr.begin() && iswspace(*--c);); sstr.erase(++c, sstr.end()); return sstr; } template <class T> inline std::basic_string<T> repeat(const std::basic_string<T>& str, unsigned int times) { std::basic_stringstream<T> ss; for (unsigned int i = 0; i < times; ++i) { ss << str; } return ss.str(); } template <class T> inline std::basic_string<T> Toupper(const std::basic_string<T>& str) { if (str.empty()) { return str; } std::basic_string<T> s(str); std::transform(s.begin(), s.end(), s.begin(), toupper); return s; } template <class T> inline std::basic_string<T> Tolower(const std::basic_string<T>& str) { if (str.empty()) { return str; } std::basic_string<T> s(str); std::transform(s.begin(), s.end(), s.begin(), tolower); return s; } template <class T> inline std::basic_string<T> replace(const std::basic_string<T>& source,const std::basic_string<T>& target,const std::basic_string<T>& replacement) { std::basic_string<T> s(source); std::basic_string<T>::size_type pos = 0; std::basic_string<T>::size_type srclen = target.size(); std::basic_string<T>::size_type dstlen = replacement.size(); while ((pos = s.find(target, pos)) != std::basic_string<T>::npos) { s.replace(pos, srclen, replacement); pos += dstlen; } return s; } template <class T> inline std::basic_string<T> between(const std::basic_string<T>& str, const std::basic_string<T>& left, const std::basic_string<T>& right) { size_t left_pos, right_pos, last_pos = 0; left_pos = str.find(left, last_pos); if (left_pos == std::basic_string<T>::npos) return std::basic_string<T>(); last_pos = left_pos + left.size(); right_pos = str.find(right, last_pos); if (right_pos == std::basic_string<T>::npos) return std::basic_string<T>(); return str.substr(left_pos + left.size(), right_pos - left_pos - left.size()); } template <class T> inline std::vector<std::basic_string<T>> between_array(const std::basic_string<T>& str, const std::basic_string<T>& left, const std::basic_string<T>&right, const bool trim_empty = false) { size_t left_pos, right_pos, last_pos = 0, len; std::vector<std::basic_string<T>> result; while (true) { left_pos = str.find(left, last_pos); if (left_pos == std::basic_string<T>::npos) { break; } else { last_pos = left_pos + left.size(); right_pos = str.find(right, last_pos); if (right_pos == std::basic_string<T>::npos) { break; } len = right_pos - left_pos - left.size(); if (len != 0 || !trim_empty) { result.push_back(str.substr(last_pos, len)); } } last_pos = right_pos + right.size(); } return result; } template <class T> inline std::basic_string<T> left(const std::basic_string<T>& str, const std::basic_string<T>& left) { std::basic_string<T> s(str); size_t pos, last_pos = 0; pos = s.find(left, last_pos); if (pos != std::basic_string<T>::npos) return s.substr(0, pos); else return std::basic_string<T>(); } template <class T> inline std::basic_string<T> right(const std::basic_string<T>& str, const std::basic_string<T>& right) { std::basic_string<T> s(str); size_t pos, last_pos = 0; pos = s.find(right, last_pos); if (pos != std::basic_string<T>::npos) { pos += right.length(); return s.substr(pos, str.length() - pos); } else return std::basic_string<T>(); } template <class T> inline bool is_start_with(const std::basic_string<T>& str, const std::basic_string<T>& src) { return str.compare(0, src.length(), src) == 0; } template <class T> inline bool is_end_with(const std::basic_string<T>& str, const std::basic_string<T>& src) { return str.compare(str.length() - src.length(), src.length(), src) == 0; }}#endif // _STRING_HELPER_HPP_INCLUDED_

test.cpp

#include "stdafx.h"#include <iostream>#include "textconv_helper.hpp"int main(){ std::wstring s = L" Hello World!! "; std::wcout << s << L" size:" << s.size() << std::endl; std::wcout << string_helper::trim(s) << L" size:" << string_helper::trim(s).size() << std::endl; std::wcout << string_helper::Toupper(s) << s.size() << std::endl; std::wcout << string_helper::Tolower(s) << s.size() << std::endl; std::wcout << string_helper::repeat<wchar_t>(s, 5) << s.size() << std::endl; std::vector<std::wstring> v; v.push_back(L"1"); v.push_back(L""); v.push_back(L"2"); v.push_back(L"3"); v.push_back(L""); // v: ["1", "", "2", "3", ""] v = string_helper::compact(v); // v: ["1", "2", "3"] for each (auto item in v) { std::wcout << item << std::endl; } std::wstring xxxx = L";"; std::wstring x = string_helper::join(v, xxxx); std::wcout << x << std::endl; v = string_helper::split(std::wstring(L"one,two,three"), std::wstring(L",")); // v: ["one", "two", "three"] for each (auto item in v) { std::wcout << item << std::endl; } std::wstring r = string_helper::replace(std::wstring(L"1-2-3-4"), std::wstring(L"-"), std::wstring(L"#")); // v: "1#2#3#4" std::wcout << r << std::endl; r = string_helper::between(s, std::wstring(L"X"), std::wstring(L"d"));// s: "ello Worl" std::wcout << r << std::endl; getchar(); return 0;}

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