Question

Fairly new to programming. I just can’t wrap my head around how to get this to work in reverse. I have a save method and an open method.
Save:

IDictionary<string, IDictionary<string, object>> pluginStates = new Dictionary<string, IDictionary<string, object>>();
signaller.RaiseSaveRequest(pluginStates); <--goes out and gets packed plugins

//loop through plugins to get values and types
//holds all of the plugin arrays
Dictionary<string, object> dictProjectState = new Dictionary<string, object>();

foreach (KeyValuePair<string,IDictionary<string,object>> plugin in pluginStates)
{ 
    //holds jsonRepresented values
    Dictionary<string, object> dictJsonRep = new Dictionary<string, object>(); 
    //holds object types
    Dictionary<string, object> dictObjRep = new Dictionary<string, object>(); 
    object[] arrayDictHolder = new object[2];  //holds all of the dictionaries
    string pluginKey = plugin.Key;
    IDictionary<string, object> pluginValue = new Dictionary<string, object>(); 
    pluginValue = plugin.Value;

    foreach (KeyValuePair<string, object> element in pluginValue)
    {
        string jsonRepresentation = JsonConvert.SerializeObject(element);
        object objType = element.Value.GetType().ToString();
        dictJsonRep.Add(element.Key, jsonRepresentation);
        dictObjRep.Add(element.Key, objType);
    }
    arrayDictHolder[0] = dictJsonRep;
    arrayDictHolder[1] = dictObjRep;
    dictProjectState.Add(pluginKey, arrayDictHolder);
}

JsonSerializer serializer = new JsonSerializer();
using (StreamWriter sw = new StreamWriter(strPathName))
using (JsonWriter writer = new JsonTextWriter(sw))
{
     serializer.Serialize(writer, dictProjectState);
}

So, when someone saves, an event handler goes out and gets the packedState of each plugin, adds it to a dictionary pluginStates. I then go through each plugin in the pluginStates, adding the key, and json string version of the value to 1 dictionary and the key, object type to another dictionary, add those 2 dictionaries to an array and then pack up a dictionary that contains the pluginKey and the array for each plugin. Reasoning: when deserializing, I’m hitting problems going from JArray to type DataTable and other types that are within the dictionary that gets passed back to the plugin to unpack itself upon opening. I’m trying to figure out how to reverse this, so that when user opens project, I have the dictProjectState and need to bring it all the way back through the code to end up with 1 dictionary containing the plugins. How do I mirror this save in the open??
Thanks!

Answer 1

I believe when you deserialize in the open function, you should get an object that can be cast to Dictionary<string, object>.

The keys of this dictionary would be the names of the plugins in your final dictioary (pluginKey in yoru save method). The values should be the object[] arrayDictHolder objects. You can cast them to object[] and then get at the two values inside (dictJsonRep and dictObjRep in your save function).

Once those values are both cast to Dictionary<string, object>(), you can iterate through the KeyValuePairs in one of them, and use the key from those pairs to get at the value store in the other dictionary.

Code would be similar to the following:

var pluginStates = new Dictionary<string, IDictionary<string, object>>();

var dictProjectState = jsonSerializer.Deserialize(reader) as Dictionary<string, object>;

foreach(var projectStatePair in dictProjectState)
{
    string pluginKey = projectStatePair.Key;
    var pluginValues = new Dictionary<string, object>();
    object[] arrayDictHolder = projectStatePair.Value as object[];
    var dictJsonRep = arrayDictHolder[0] as Dictionary<string, object>;
    var dictObjRep =  arrayDictHolder[1] as Dictionary<string, object>;
    foreach(var JsonRepPair in dictJsonRep)
    {
        string jsonRepresentation = JsonRepPair.Value;
        // We know both dictionaries have the same keys, so
        // get the objType for this JsonRepresentation
        object objType = dictObjRep[JsonRepPair.Key];
        // Since you're serializing objType to a string, you'll need
        // to get the actual Type before calling DeserializeObject.
        Type jsonType = System.Type.GetType(objType as string);
        object value = JsonConvert.DeserializeObject( jsonRepresentation, jsonType );
        pluginValues.Add( JsonRepPair.Key );
    }
    pluginStates.Add( pluginKey, pluginValues );
}

Note: You are currently setting objType to element.Value.GetType().ToString(); in your save function. You will either need to update save() to set it to element.Value.GetType(); or convert the type strings back to actual Types before trying to deserialize.

Note: I am not very familiar with the Json libraries. The above code is focused on creating your pluginStates dictionary out of the deserialized results. You will need to handle the creation of your JsonSerializer and make sure you close any streams after you’ve deserialized them. You may also need to tweak the actual deserialization calls to get the desired results.

Update: Added conversion of objType to actual System.Type object.