RapidXml 讀取檔案並遍歷節點的所有屬性
阿新 • • 發佈：2019-01-11
RapidXml 試圖成為最快的 XML DOM 解析工具包，同時保證解析結果的可用性、可移植性以及與 W3C 標準的相容性。RapidXml 使用 C++ 編寫，因此在操作同一資料時，其解析速度接近於 strlen() 函式。
整個解析工具包包含在一個頭檔案中，所以使用時不用編譯也不用連線。要想使用 RapidXml 只要包含 rapidxml.hpp 即可，當然如果要用附加功能（如列印函式），你可以包含 rapidxml_print.hpp 檔案。
RapidXml 為採用C++語言操作XML提供了機遇，同時結合XMPP協議也開啟了諸如Wt、CxServer等基於C++的網路應用在即時通訊領域的更寬廣的發展空間。
測試程式程式碼：
測試示例：
讀取xml檔案，並遍歷所有節點的所有屬性。xml的檔案內容如下：
<?xml version="1.0" encoding="UTF-8"?> <EllipsoidParams> <Datum Name="BeiJing54" SemiMajorAxis="6378245.0" Flattening="298.3"/> <Datum Name="XiAn80" SemiMajorAxis="6378140.0" Flattening="298.257"/> <Datum Name="CGCS2000" SemiMajorAxis="6378137.0" Flattening="298.257222101"/> <Datum Name="WGS-84" SemiMajorAxis="6378137.0" Flattening="298.257223563"/> <Datum Name="WGS-72" SemiMajorAxis="6378135.0" Flattening="298.26"/> <Datum Name="WGS-66" SemiMajorAxis="6378145.0" Flattening="298.25"/> <Datum Name="WGS-60" SemiMajorAxis="6378165.0" Flattening="298.3"/> <Datum Name="Krassovsky" SemiMajorAxis="6378245.0" Flattening="298.3"/> <Datum Name="International" SemiMajorAxis="6378388.0" Flattening="297.0"/> <Datum Name="MERIT-83" SemiMajorAxis="6378137.0" Flattening="298.257"/> <Datum Name="SGS85" SemiMajorAxis="6378136.0" Flattening="298.257"/> <Datum Name="GRS80" SemiMajorAxis="6378137.0" Flattening="298.257222101"/> <Datum Name="GRS75" SemiMajorAxis="6378140.0" Flattening="298.257"/> <Datum Name="Airy 1830" SemiMajorAxis="6377563.396" Flattening="299.3249753150"/> <Datum Name="Modified Airy" SemiMajorAxis="6377340.189" Flattening="299.32493736548"/> <Datum Name="Aust_SA" SemiMajorAxis="6378160.0" Flattening="298.25"/> <Datum Name="Bessel 1841" SemiMajorAxis="6377397.155" Flattening="299.15281285"/> <Datum Name="Clarke 1880" SemiMajorAxis="6378249.145" Flattening="293.4663"/> <Datum Name="Clarke 1866" SemiMajorAxis="6378206.4" Flattening="294.9786982139"/> <Datum Name="GRS67" SemiMajorAxis="6378160.0" Flattening="298.247167427"/> <Datum Name="APL4.9" SemiMajorAxis="6378137.0" Flattening="298.25"/> <Datum Name="Andrae" SemiMajorAxis="6377104.43" Flattening="300.0"/> <Datum Name="Bessel_nam" SemiMajorAxis="6377483.865" Flattening="299.1528128"/> <Datum Name="CPM" SemiMajorAxis="6375738.7" Flattening="334.29"/> <Datum Name="Delamber" SemiMajorAxis="6376428.0" Flattening="311.5"/> <Datum Name="Engelis" SemiMajorAxis="6378136.05" Flattening="298.2566"/> <Datum Name="Everest30" SemiMajorAxis="6377276.345" Flattening="300.8017"/> <Datum Name="Everest48" SemiMajorAxis="6377304.063" Flattening="300.8017"/> <Datum Name="Everest56" SemiMajorAxis="6377301.243" Flattening="300.8017"/> <Datum Name="Everest69" SemiMajorAxis="6377295.664" Flattening="300.8017"/> <Datum Name="EverestSS" SemiMajorAxis="6377298.556" Flattening="300.8017"/> <Datum Name="Fischer60" SemiMajorAxis="6378166.0" Flattening="298.3"/> <Datum Name="Fischer60m" SemiMajorAxis="6378155.0" Flattening="298.3"/> <Datum Name="Fischer68" SemiMajorAxis="6378150.0" Flattening="298.3"/> <Datum Name="Helmert" SemiMajorAxis="6378200.0" Flattening="298.3"/> <Datum Name="Hough" SemiMajorAxis="6378270.0" Flattening="297.0"/> <Datum Name="IAU76" SemiMajorAxis="6378140.0" Flattening="298.257"/> <Datum Name="Kaula" SemiMajorAxis="6378163.0" Flattening="298.24"/> <Datum Name="Lerch" SemiMajorAxis="6378139.0" Flattening="298.257"/> <Datum Name="Maupertius" SemiMajorAxis="6397300.0" Flattening="191.0"/> <Datum Name="New_intl" SemiMajorAxis="6378157.5" Flattening="298.24961539"/> <Datum Name="NWL9D" SemiMajorAxis="6378145.0" Flattening="298.25"/> <Datum Name="Plessis" SemiMajorAxis="6376523.0" Flattening="0.0"/> <Datum Name="Southeast_asia" SemiMajorAxis="6378155.0" Flattening="298.3000002409"/> <Datum Name="Sphere" SemiMajorAxis="6370997.0" Flattening="298.257"/> <Datum Name="Walbeck" SemiMajorAxis="6376896.0" Flattening="302.7800001817"/> </EllipsoidParams>
測試程式程式碼：
#include <tchar.h> #include <string> #include <iostream> #include "rapidxml/rapidxml.hpp" #include "rapidxml/rapidxml_utils.hpp"//rapidxml::file #include "rapidxml/rapidxml_print.hpp"//rapidxml::print using namespace rapidxml; std::string ReadFile(const char* fileName) { std::string strBuffer; FILE *fp = fopen(fileName, "rb"); if(NULL == fp) { return ""; } char buf[1024]; while(true) { const size_t byteRead = fread(buf, 1, sizeof(buf), fp); if(0 == byteRead) { break; } strBuffer.insert(strBuffer.end(), buf, buf+byteRead); } fclose(fp); return strBuffer; } // int ReadFileAndTraversal() { //讀取檔案內容 std::string szFileBuf = ReadFile("./Ellipsoid.xml"); //使用rapidxml::file讀取檔案更方便 rapidxml::file<> fdoc("Ellipsoid.xml"); //列印讀取的內容 std::cout << fdoc.data() << std::endl; rapidxml::xml_document<> doc; doc.parse<0>(fdoc.data()); //doc.parse<0>(szFileBuf.c_str()); //列印整個XML內容 std::cout << doc.name() << std::endl; //在XML文件中尋找第一個節點 const rapidxml::xml_node<> *ellipsoid = doc.first_node("EllipsoidParams"); if(NULL == ellipsoid) { return -1; } //遍歷所有橢球資訊 for(rapidxml::xml_node<> *datum = ellipsoid->first_node("Datum"); NULL != datum; datum = datum->next_sibling()) { //遍歷單個橢球的所有屬性 std::string szTmp(""); for(rapidxml::xml_attribute<char> * attr = datum->first_attribute("Name"); attr != NULL; attr = attr->next_attribute()) { szTmp.append(attr->name());//name() value()返回的字串不會去掉首尾的空白字元 szTmp.append(": "); szTmp.append(attr->value()); szTmp.append(", "); } std::cout << szTmp.c_str() << std::endl; } return 0; } // int _tmain(int argc, _TCHAR* argv[]) { //讀取檔案並列印整個檔案 ReadFileAndTraversal(); system("pause"); return 0; }