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c++ json jsoncpp

Iterating through objects in JsonCpp

I have a C++ application that uses jsoncpp to decode a JSON string. I have created the following function but it only shows me the top level objects…

How do I get it to dump the entire object list?

–Function–

SaveJSON( json_data ); 
bool CDriverConfigurator::PrintJSONTree( Json::Value & root, unsigned short depth /* = 0 */)
{
printf( " {type=[%d], size=%d} ", root.type(), root.size() );
if( root.size() > 0 ) {
for( Json::ValueIterator itr = root.begin() ; itr != root.end() ; itr++ ) {
PrintJSONTree( itr.key(), depth+1 );
}
return true;
}
// Print depth.
for( int tab = 0 ; tab < depth; tab++) {
printf( "-");
}
if( root.isString() ) {
printf( " %s", root.asString().c_str() );
} else if( root.isBool() ) {
printf( " %d", root.asBool() );
} else if( root.isInt() ) {
printf( " %d", root.asInt() );
} else if( root.isUInt() ) {
printf( " %d", root.asUInt() );
} else if( root.isDouble() ) {
printf( " %f", root.asDouble() );
}
else
{
printf( " unknown type=[%d]", root.type() );
}
printf( "\n" );
return true;
}

— Input —-

{
"modules":[
{
"config":{
"position":[
129,
235
]
},
"name":"Modbus Task",
"value":{
"DeviceID":"This is the name",
"Function":"01_READ_COIL_STATUS",
"Length":"99",
"Scan":"111",
"Type":"Serve"
}
},
{
"config":{
"position":[
13,
17
]
},
"name":"Modbus Connection",
"value":{
"Baud":"9600",
"timeout":"2.5"
}
},
{
"config":{
"position":[
47,
145
]
},
"name":"Modbus Device",
"value":{
"DeviceID":"55"
}
},
{
"config":{
"position":[
363,
512
]
},
"name":"Function Something",
"value":{
}
},
{
"config":{
"position":[
404,
701
]
},
"name":"Function Something",
"value":{
}
}
],
"properties":{
"Blarrg":"",
"description":"",
"name":"Modbus"
},
"wires":[
{
"src":{
"moduleId":1,
"terminal":"modbus.connection.output"
},
"tgt":{
"moduleId":2,
"terminal":"modbus.connection.input"
}
},
{
"src":{
"moduleId":2,
"terminal":"modbus.device.output"
},
"tgt":{
"moduleId":0,
"terminal":"modbus.device.output"
}
},
{
"src":{
"moduleId":3,
"terminal":"dataOut"
},
"tgt":{
"moduleId":4,
"terminal":"dataIn"
}
},
{
"src":{
"moduleId":3,
"terminal":"dataIn"
},
"tgt":{
"moduleId":0,
"terminal":"data1"
}
}
]
}

–Output–

{type=[7], size=3} {type=[4], size=0} - modules
{type=[4], size=0} - properties
{type=[4], size=0} - wires

You have some errors related to seemingly not having a great handle on recursion or the key->value nature of JSON and how that relates to the library you’re using. I haven’t tested this code at all, but it should work better.

void CDriverConfigurator::PrintJSONValue( const Json::Value &val )
{
if( val.isString() ) {
printf( "string(%s)", val.asString().c_str() );
} else if( val.isBool() ) {
printf( "bool(%d)", val.asBool() );
} else if( val.isInt() ) {
printf( "int(%d)", val.asInt() );
} else if( val.isUInt() ) {
printf( "uint(%u)", val.asUInt() );
} else if( val.isDouble() ) {
printf( "double(%f)", val.asDouble() );
}
else
{
printf( "unknown type=[%d]", val.type() );
}
}
bool CDriverConfigurator::PrintJSONTree( const Json::Value &root, unsigned short depth /* = 0 */)
{
depth += 1;
printf( " {type=[%d], size=%d}", root.type(), root.size() );
if( root.size() > 0 ) {
printf("\n");
for( Json::Value::const_iterator itr = root.begin() ; itr != root.end() ; itr++ ) {
// Print depth.
for( int tab = 0 ; tab < depth; tab++) {
printf("-");
}
printf(" subvalue(");
PrintJSONValue(itr.key());
printf(") -");
PrintJSONTree( *itr, depth);
}
return true;
} else {
printf(" ");
PrintJSONValue(root);
printf( "\n" );
}
return true;
}