thanks again. Much appreciate the intro to json objects in v8

On Jun 21, 2012, at 6:11 AM, Matthias Ernst <[email protected]> wrote:

> On Thu, Jun 21, 2012 at 12:03 PM, Mark Essel <[email protected]> wrote:
>> Thanks for calling it out Matthias. Assume it works for nested properties:
>> 
>>> obj_handle->Get(propertyName)->Get(propertyName)
> 
> Almost. Get is defined in Object, but returns a Handle<Value>.
> So you need to test (value_handle->IsObject()) and cast
> (value_handle.As<Object>).
> 
> Handle<Value> v = ... parse json ...
> for (const string& property_name : path) {
>  if (!v->IsObject()) {
>    v = v8::Undefined();
>    break;
>  }
>  v = (v.As<Object>)->Get(property_name);
> }
> 
> or somesuch.
> 
>> 
>> I was hoping for a nested map of maps
>> obj[pname1][pname2][pname3]
>> 
>> 
>> On Jun 21, 2012, at 5:47 AM, Matthias Ernst <[email protected]> wrote:
>> 
>>> On Thu, Jun 21, 2012 at 12:49 AM, Mark Essel <[email protected]> wrote:
>>>> Just wanted to say thanks for asking this question Guilherme. I know have
>>>> access to a straight forward json parser for my native module.
>>>> when walking the jsonObject that results from the parsing do you loop over
>>>> properties to find the keys of interest or is there a rapid/hashlike lookup
>>>> available?
>>> 
>>> You're using it already: obj_handle->Get(propertyName)
>>> 
>>>> 
>>>> ie
>>>> Handle<Value> parseJson(Handle<Value> jsonString) {
>>>>     HandleScope scope;
>>>> 
>>>>     Handle<Context> context = Context::GetCurrent();
>>>>     Handle<Object> global = context->Global();
>>>> 
>>>>     Handle<Object> JSON = global->Get(String::New("JSON"))->ToObject();
>>>>     Handle<Function> JSON_parse =
>>>> Handle<Function>::Cast(JSON->Get(String::New("parse")));
>>>> 
>>>>     // return JSON.parse.apply(JSON, jsonString);
>>>>     return scope.Close(JSON_parse->Call(JSON, 1, &jsonString));
>>>> }
>>>> 
>>>> then on the returned Handle<Value> obj
>>>> 
>>>> Local<Array> propertyNames = obj->GetPropertyNames();
>>>> for (int i=0;i < propertyNames->Length();++i) {
>>>>     // check if propertyName matches one I'm interested in
>>>> }
>>>> 
>>>> or recursively walk the json tree
>>>> Handle<Value> findMatchingValue(const string &key, Handle<Value> obj) {
>>>>     HandleScope scope;
>>>>     Handle<Value> rval;
>>>>     Local<Array> propertyNames = obj->GetPropertyNames();
>>>>     for (int i=0;i < propertyNames->Length();++i) {
>>>>         String::Utf8Value name = properNames->Get(i);
>>>>         if (name == *obj) { // check if propertyName matches one I'm
>>>> interested in, not sure this will compile/function as desired
>>>>             rval = currentValue;
>>>>         }
>>>>         // if value type is an object or has children, gotta figure how to
>>>> do this
>>>>             rval = findMatchingValue(key,value)
>>>>     }
>>>> }
>>>> 
>>>> 
>>>> 
>>>> 
>>>> On Sunday, June 10, 2012 5:30:10 PM UTC-4, Guilherme Silva wrote:
>>>>> 
>>>>> Thanks everybody for your replies! I want to create a Script Manager that
>>>>> encapsulates V8 and abstracts both js from json files ;).
>>>> 
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