Simple JSON Implementation

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The reason I made this (except for the fun of it) is that I found a couple of people had issues with incorporating QJson in their projects (be it what it may). I reserve no copyrights to this implementation so you are all welcome to ctrl+c ctrl+v and do as you see fit with it.

JsonObject.hpp

#ifndef JSONOBJECT_HPP

  1. define JSONOBJECT_HPP
  1. include <QVariant>

typedef QVariantList JsonArray;

class JsonObject { public:

static const QString null;
static const QString True;
static const QString False;

JsonObject(QString jsonData = "");

QString toString() const;

void put(const QString& id,JsonObject obj);

void put(const QString& id,QString value);
void put(const QString& id,int value);
void put(const QString& id,double value);
void put(const QString& id,qlonglong value);
void put(const QString& id,JsonArray value);

JsonObject getObject(const QString& id, bool *ok = NULL) const;

QString getString(const QString& id, bool *ok = NULL) const;
int getInt(const QString& id, bool *ok = NULL) const;
double getDouble(const QString& id, bool *ok = NULL) const;
qlonglong getLong(const QString& id, bool *ok = NULL) const;
JsonArray getArray(const QString& id, bool *ok = NULL) const;

bool isNull(const QString& id) const;

QVariantMap getRawData() const; protected:

void setRawData(QVariantMap data);

private:

QString stringFromList(const JsonArray& array) const;
QString getKey(QString& data);
QString getValue(QString& data);
JsonArray parseArray(QString data);

QVariantMap objectData; };

  1. endif // JSONOBJECT_HPP

Here's the cpp code:

JsonObject.cpp

#include "JsonObject.hpp"

  1. include <QStringList>

QString JsonObject::toString() const {

QString result = "{";
QStringList keys = objectData.keys();
for(int i = 0; i < keys.count(); +i)
{
QVariant data = objectData.value(keys.at(i));
switch(data.type())
{
case QVariant::Map:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
JsonObject obj;
obj.setRawData(data.toMap());
result.append(obj.toString());
result.append(',');
}
break;
case QVariant::String:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
if(data.toString()  null || data.toString()  True
|| data.toString() == False)
result.append(data.toString());
else
{
result.append('"');
result.append(data.toString());
result.append('"');
}
result.append(',');
}
break;
case QVariant::Int:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1").arg(data.toInt()));
result.append(',');
}
break;
case QVariant::Double:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1").arg(data.toDouble()));
result.append(',');
}
break;
case QVariant::LongLong:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(QString("%1").arg(data.toLongLong()));
result.append(',');
}
break;
case QVariant::List:
{
result.append('"');
result.append(keys.at(i));
result.append('"');
result.append(':');
result.append(stringFromList(data.toList()));
result.append(',');
}
break;
default:
break;
}
}
if(result.endsWith(','))
result.remove(result.length() - 1,1);
result.append("}");
return result;

}

void JsonObject::put(const QString& id,JsonObject obj) {

objectData.insert(id,QVariant(obj.getRawData()));

}

void JsonObject::put(const QString& id,QString value) {

if(value.startsWith('"'))
value.remove(0,1);
if(value.endsWith('"'))
value.remove(value.length() - 1,1);
objectData.insert(id,QVariant(value));

}

void JsonObject::put(const QString& id,int value) {

objectData.insert(id,QVariant(value));

}

void JsonObject::put(const QString& id,double value) {

objectData.insert(id,QVariant(value));

}

void JsonObject::put(const QString& id,qlonglong value) {

objectData.insert(id,QVariant(value));

}

void JsonObject::put(const QString& id,JsonArray value) {

objectData.insert(id,QVariant(value));

}

JsonObject JsonObject::getObject(const QString& id, bool *ok) const {

JsonObject result;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Map)
{
result.setRawData(data.toMap());
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

QString JsonObject::getString(const QString& id, bool *ok) const {

QString result = "";
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::String)
{
result = data.toString();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

int JsonObject::getInt(const QString& id, bool *ok) const {

int result = 0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Int)
{
result = data.toInt();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

double JsonObject::getDouble(const QString& id, bool *ok) const {

double result = 0.0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::Double)
{
result = data.toDouble();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

qlonglong JsonObject::getLong(const QString& id, bool *ok) const {

qlonglong result = 0;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::LongLong)
{
result = data.toLongLong();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

JsonArray JsonObject::getArray(const QString& id, bool *ok) const {

JsonArray result;
bool isOk = false;
if(objectData.contains(id))
{
QVariant data = objectData.value(id);
if(data.type() == QVariant::List)
{
result = data.toList();
isOk = true;
}
}
if(ok != NULL)
*ok = isOk;
return result;

}

bool JsonObject::isNull(const QString& id) const {

if(objectData.contains(id))
{
if(objectData.value(id).type()  QVariant::String)
           return objectData.value(id).toString()  null;
return false;
}
return true;

}

QVariantMap JsonObject::getRawData() const {

return objectData;

}

void JsonObject::setRawData(QVariantMap data) {

objectData = data;

}

QString JsonObject::stringFromList(const JsonArray& array) const {

QString result = "[";
for(int i = 0; i < array.count();i)
{
QVariant data = array.at(i);
switch(data.type())
{
case QVariant::Map:
{
JsonObject obj;
obj.setRawData(data.toMap());
result.append(obj.toString());
result.append(',');
}
break;
case QVariant::String:
{
if(data.toString()  null || data.toString()  False || data.toString() == True)
result.append(data.toString());
else
{
result.append('"');
result.append(data.toString());
result.append('"');
}
result.append(',');
}
break;
case QVariant::Int:
{
result.append(QString("%1").arg(data.toInt()));
result.append(',');
}
break;
case QVariant::Double:
{
result.append(QString("%1").arg(data.toDouble()));
result.append(',');
}
break;
case QVariant::LongLong:
{
result.append(QString("%1").arg(data.toLongLong()));
result.append(',');
}
break;
case QVariant::List:
{
result.append(stringFromList(data.toList()));
result.append(',');
}
break;
default:
break;
}
}
if(result.endsWith(','))
result.remove(result.length() - 1,1);
result.append("]");
return result;

}

QString JsonObject::getKey(QString& data) {

QString key = "";
int index = data.indexOf(':');
if(index >= 0)
{
key = data.mid(0,index);
data.remove(0,index);
if(data.startsWith(':'))
data.remove(0,1);
}
if(key.startsWith('"'))
key.remove(0,1);
if(key.endsWith('"'))
key.remove(key.length() - 1,1);
return key;

}

QString JsonObject::getValue(QString& data) {

QString value = "";
if(data.startsWith('{'))//object
{
int index = data.indexOf('}');
if(index >= 0)
{
value.append(data.mid(0,index 1));
data.remove(0,index + 1);
while(value.count('{') > value.count('}'))
{
index = data.indexOf('}');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
}
else
{
value = "";
break;
}
}
if(data.startsWith(','))
data.remove(0,1);
}
}
else if(data.startsWith('['))//Array
{
int index = data.indexOf(']');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
while(value.count('[') > value.count(']'))
{
index = data.indexOf(']');
if(index >= 0)
{
value.append(data.mid(0,index + 1));
data.remove(0,index + 1);
}
else
{
value = "";
break;
}
}
if(data.startsWith(','))
data.remove(0,1);
}
}
else
{
int index = data.indexOf(',');
if(index >= 0)
{
value = data.mid(0,index);
data.remove(0,index);
if(data.startsWith(','))
data.remove(0,1);
}
else if(!data.contains(','))
{
value = data;
data.clear();
}
}
return value;

}

JsonArray JsonObject::parseArray(QString data) {

JsonArray result;
if(data.startsWith('[') && data.endsWith(']'))
{
data.remove(0,1);
data.remove(data.length() - 1,1);
while(data.length() > 0)
{
QString value = getValue(data);
if(value.startsWith('{'))//Object
{
JsonObject obj(value);
result.append(QVariant(obj.getRawData()));
}
else if(value.startsWith('['))//Array
{
JsonArray array = parseArray(value);
result.append(QVariant(array));
}
else if(value.startsWith('"'))//String
{
value.remove(0,1);
if(value.endsWith('"'))
value.remove(value.length() - 1,1);
result.append(QVariant(value));
}
else if(value  null)
               result.append(QVariant(null));
           else if(value  True)
result.append(QVariant(True));
else if(value == False)
result.append(QVariant(False));
else//Number
{
if(value.contains('.'))//double
{
bool ok;
double doubleValue = value.toDouble(&ok);
if(ok)
result.append(QVariant(doubleValue));
else
result.append(QVariant(0.0));
}
else//int || long
{
bool ok;
int intValue = value.toInt(&ok);
if(ok)
result.append(QVariant(intValue));
else
{
qlonglong longValue = value.toLongLong(&ok);
if(ok)
result.append(QVariant(longValue));
else
result.append(QVariant(0));
}
}
}
}
}
return result;

}

JsonObject::JsonObject(QString jsonData) {

if(jsonData.startsWith('{') && jsonData.endsWith('}'))
{
jsonData.remove(0,1);
jsonData.remove(jsonData.length() - 1,1);
while(jsonData.length() > 0)
{
QString key = getKey(jsonData);
QString value = getValue(jsonData);
if(value.startsWith('{'))//Object
this->put(key,JsonObject(value));
else if(value.startsWith('['))//Array
{
JsonArray array = parseArray(value);
this->put(key,array);
}
else if(value.startsWith('"'))//String
this->put(key,value);
else if(value  null)
               this->put(key,null);
           else if(value  True)
this->put(key,True);
else if(value == False)
this->put(key,False);
else//Number
{
if(value.contains('.'))//double
{
bool ok;
double doubleValue = value.toDouble(&ok);
if(ok)
this->put(key,doubleValue);
else
this->put(key,0.0);
}
else//int || long
{
bool ok;
int intValue = value.toInt(&ok);
if(ok)
this->put(key,intValue);
else
{
qlonglong longValue = value.toLongLong(&ok);
if(ok)
this->put(key,longValue);
else
this->put(key,0);
}
}
}
}
}

}

const QString JsonObject::null = "null"; const QString JsonObject::True = "true"; const QString JsonObject::False = "false";