当前位置：首页 > news >正文

Qt中使用RapidJSON

news 来源：原创 2024/9/20 19:57:55

RapidJSON 是一个 C++ 的 JSON 解析器及生成器。它的灵感来自 RapidXml。
RapidJSON 小而全。它同时支持 SAX 和 DOM 风格的 API。SAX 解析器只有约 500 行代码。
http://rapidjson.org/zh-cn/官网

使用代码如下：实现Document转出到QVariantMap


#include <QtCore/QCoreApplication>
#include "rapidjson/document.h"
#include "rapidjson/writer.h"
#include "rapidjson/stringbuffer.h"
#include <iostream>#include "handlerapidjson.h"
#include <QMap>
#include <QByteArray>
#include <QVariantMap>using namespace rapidjson; QString getString(rapidjson::Document &doc, QString key)
{QString str = "";if (doc.HasMember(key.toLocal8Bit().data()) && doc[key.toLocal8Bit().data()].IsString()){str = QString::fromLocal8Bit(doc[key.toLocal8Bit().data()].GetString());}return str;}QString getStringFromObj(rapidjson::Value& obj, QString key)
{QString str = "";if (obj.HasMember(key.toLocal8Bit().data()) && obj[key.toLocal8Bit().data()].IsString()){str = QString::fromLocal8Bit(obj[key.toLocal8Bit().data()].GetString());}return str;}QString valueToString(const rapidjson::Value &objValue)
{QString rstr;if (objValue.IsString()){rstr = QString(objValue.GetString()); }else if (objValue.IsInt()){rstr = QString("%1").arg(objValue.GetInt());}else if (objValue.IsDouble()){rstr = QString("%1").arg(objValue.GetDouble());}else if (objValue.IsBool()){rstr = QString("%1").arg(objValue.GetBool());}else if (objValue.IsNumber()){rstr = QString("%1").arg(objValue.GetInt64());}else if (objValue.IsInt64()){rstr = QString("%1").arg(objValue.GetInt64());}return rstr;
}QVariantMap pareDoc(rapidjson::Document &document)
{//暂时只支持一层QVariantMap rmap;for (rapidjson::Value::ConstMemberIterator itr = document.MemberBegin(); itr != document.MemberEnd(); ++itr){const rapidjson::Value& objKey = itr->name;const rapidjson::Value& objValue = itr->value;QString key = QString(objKey.GetString());QString valuestr;if (objValue.IsObject()){QVariantMap objmap;for (rapidjson::Value::ConstMemberIterator objIt = itr->value.MemberBegin(); objIt != itr->value.MemberEnd(); ++objIt){const rapidjson::Value& childobjKey = objIt->name;const rapidjson::Value& childobjValue = objIt->value;QString childkey = QString(childobjKey.GetString());QString childvaluestr = valueToString(childobjValue);objmap.insert(childkey, childvaluestr);}rmap.insert(key,objmap);}else if (objValue.IsArray()){QVariantList tmplist;for (rapidjson::SizeType i = 0; i < objValue.Size(); ++i) {const rapidjson::Value& element = objValue[i];if (element.IsObject()){//解析对象QVariantMap objmap;for (rapidjson::Value::ConstMemberIterator objIt = element.MemberBegin(); objIt != element.MemberEnd(); ++objIt){const rapidjson::Value& childobjKey = objIt->name;const rapidjson::Value& childobjValue = objIt->value;QString childkey = QString(childobjKey.GetString());QString childvaluestr = valueToString(childobjValue);objmap.insert(childkey, childvaluestr);}tmplist << objmap;}else{	//解析数组valuestr = valueToString(element);tmplist << valuestr;}}rmap.insert(key,tmplist);}else {valuestr = valueToString(objValue);rmap.insert(key,valuestr);}}return rmap;}void writeTest()
{rapidjson::Document document;  document.SetArray();  QString sss = "sss";rapidjson::Document::AllocatorType& allocator = document.GetAllocator();  // 创建一个JSON对象并添加到数组中  rapidjson::Value obj1(rapidjson::kObjectType);  obj1.AddMember(rapidjson::Value().SetString(sss.toLocal8Bit().data(),allocator), rapidjson::Value().SetString(sss.toLocal8Bit().data(),allocator), allocator);  obj1.AddMember("age", 30, allocator);  document.PushBack(obj1, allocator);  // 创建另一个JSON对象并添加到数组中  rapidjson::Value obj2(rapidjson::kObjectType);  obj2.AddMember("name", "Doe", allocator);  obj2.AddMember("age", 25, allocator);  //document.PushBack(obj2, allocator);  rapidjson::Value obj3(rapidjson::kArrayType);obj3.PushBack(obj2, allocator); document.SetObject();document.AddMember("keyid", obj3, allocator);  // 将JSON数组转换为字符串  rapidjson::StringBuffer buffer;  rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);  document.Accept(writer);  std::cout << buffer.GetString() << std::endl;
}int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);const char* json = "{\"project\":\"rapidjson\",\"stars\":10, \"obj\": {\"a\":\"1\",\"c\":1720243638463},\"list\":[1,2,3,4], \"listobj\":[{\"a\":\"1\",\"c\":1720243638463}]}";Document d;d.Parse(json);QVariantMap rmap = pareDoc(d);return 1;}