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Issue deserializing a date represented as a string in document from Cosmos DB

I currently have a C# application that queries Cosmos DB. In the database everything is stored as strings. When I query the container for the document and pull out the information it looks like the deserialization process is treating it like a date and its applying the Date Time Offset. Strange part is this process of querying the DB never converts it to a date? I would like it to just pass through the app as its stored in Cosmos.
Here is the document shape in Cosmos:
{
"id": "uniqueId",
"MyDate" : "2021-07-24T23:59:00+0000"
}
Here is the code that connects to CosmosDB
using(var client = new CosmosClient("EndPoint","Key")
{
string sqlQueryText = "Select * From c Where .... ";
QueryDefinition querySQL = new QueryDefination(sqlQueryText);
var container = client.GetContainer("databaseId", "ContainerId");
var iii = container.GetItemQueryIterator<Document>(querySQL);
var myList = new List<Document>();
while(iii.HasMoreResults)
{
FeedResponse<Document> currentRS = iii.ReadNextAsync().Result;
foreach(Document doc in currentRS)
{
myList.Add(doc);
}
}
}
Here is the Output of the this process in C#, By output I mean if you look at the myList Object and inspect the Mydate Property you will see this string below.
"07/24/2021 19:59:00"
which is the date & time with the date time offset.
How do I prevent this?
This application should just pass the string straight through with no regard for "Real Type".
I would just like to get "2021-07-24T23:59:00+0000"

Unity C# Parse Query Problems

I'm new to Parse and Facebook SDK's and when looking through the documentation and other posts I still can't get the query working. When using a query to get the data back from the server it isn't allowing me to put the information into variables. For example, when the code is called, all that appears in the console is: "Parse.ParseObject".
var query = ParseObject.GetQuery("DataRetrieval")
.WhereEqualTo("RetrievalID", retrievalID);
query.FindAsync().ContinueWith(t =>
{
IEnumerable<ParseObject> createdAt = t.Result;
foreach ( var obj in createdAt)
{
Debug.Log(obj);
DateTime createdAtTime = obj.Get<DateTime>("createdAt");
Debug.Log(createdAtTime);
DateTime? updatedAt = dataRetrieval.UpdatedAt;
Debug.Log(updatedAt);
}
});
I've tried multiple different ways to get this to work. I'm also looking to retrieve data which I have stored, but I'm assuming that it will be done in the same/similar way to this once it's working.

Parse & Unity 3D : Update an existing row

Using the example code from the Unity Developer Guide | Parse
# https://www.parse.com/docs/unity_guide#objects-updating
// Create the object.
var gameScore = new ParseObject("GameScore")
{
{ "score", 1337 },
{ "playerName", "Sean Plott" },
{ "cheatMode", false },
{ "skills", new List<string> { "pwnage", "flying" } },
};
gameScore.SaveAsync().ContinueWith(t =>
{
// Now let's update it with some new data. In this case, only cheatMode
// and score will get sent to the cloud. playerName hasn't changed.
gameScore["cheatMode"] = true;
It just adds a new row and leaves the original row unchanged.
I guess i'm thinking Parse would do something "SQL like" such as UPDATE where primaryKey = 123.
Searching for an answer i found this code #
https://parse.com/questions/updating-a-field-without-retrieving-the-object-first, but there was no example in C#. All attempts to port this to C# result in multiple syntax errors.
UnityScript:
// Create a pointer to an object of class Point with id dlkj83d
var Point = Parse.Object.extend("Point");
var point = new Point();
point.id = "dlkj83d";
// Set a new value on quantity
point.set("quantity", 6);
// Save
point.save(null, {
success: function(point) {
// Saved successfully.
},
error: function(point, error) {
// The save failed.
// error is a Parse.Error with an error code and description.
}
});
Does Parse have some way to update a row that already exists using C#? And where is it in the docs? And how can their own example be so useless?

One of the posts related to my question stated "retrieve the object, then write it back with the changes" and i had not the faintest idea how to execute the stated objective (especially after the epic fail of Parse Documentation's example code)
Here is what i have been able to figure out and make work:
var query = new ParseQuery<ParseObject>("Tokens")
.WhereEqualTo ("objectId", "XC18riofu9");
query.FindAsync().ContinueWith(t =>
{
var tokens = t.Result;
IEnumerator<ParseObject> enumerator = tokens.GetEnumerator();
enumerator.MoveNext();
var token = enumerator.Current;
token["power"] = 20;
return token.SaveAsync();
}).Unwrap().ContinueWith(t =>
{
// Everything is done!
//Debug.Log("Token has been updated!");
});
the first part retrieves the object with the stated objectId, the second part sets the fields in the object. The third part reports all is well with the operation.
it's a monkey see, monkey do understanding at this point being that i do not understand the finer points in the code.
the code can be tested by creating a class named "Tokens". in that class create a tokenName field and a power field. make a few rows with Fire, water, mud as the tokenNames. Replace the objectId in the .WhereEqualTo clause with a valid objectId or any other search parameters you like. Execute the code and observe the changes in the Parse Data Browser.
For extra credit create the class required to implement the example code from the Chaining Tasks Together section of Parse's Documentation.
https://www.parse.com/docs/unity_guide#tasks-chaining

Using Accord.Net's Codification Object to Codify second data set

I am trying to figure out how to use the Accord.Net Framework to make a bayesian prediction using the machine learning NaiveBayes class. I have followed the example code listed in the documentation and have been able to create the model from the example.
What I can't figure out is how to make a prediction based on that model.
The way the Accord.Net framework works is that it translates a table of strings into numeric symolic representation of those strings using a class called Codification. Here is how I create inputs and outputs DataTable to train the model (90% of this code is straight from the example):
var dt = new DataTable("Categorizer");
dt.Columns.Add("Word");
dt.Columns.Add("Category");
foreach (string category in categories)
{
rep.LoadTrainingDataForCategory(category,dt);
}
var codebook = new Codification(dt);
DataTable symbols = codebook.Apply(dt);
double[][] inputs = symbols.ToArray("Word");
int[] outputs = symbols.ToIntArray("Category").GetColumn(0);
IUnivariateDistribution[] priors = {new GeneralDiscreteDistribution(codebook["Word"].Symbols)};
int inputCount = 1;
int classCount = codebook["Category"].Symbols;
var target = new NaiveBayes<IUnivariateDistribution>(classCount, inputCount, priors);
target.Estimate(inputs, outputs);
And this all works successfully. Now, I have new input that I want to test against the trained data model I just built. So I try to do this:
var testDt = new DataTable("Test Data");
testDt.Columns.Add("Word");
foreach (string token in tokens)
{
testDt.Rows.Add(token);
}
DataTable testDataSymbols = codebook.Apply(testDt);
double[] testData = testDataSymbols.ToArray("Word").GetColumn(0);
double logLikelihood = 0;
double[] responses;
int cat = target.Compute(testData, out logLikelihood, out responses);
Notice that I am using the same codebook object that I was using previously when I built the model. I want the data to be codified using the same codebook as the original model, otherwise the same word might be encoded with two completely different values (the word "bob" in the original model might correspond to the number 23 and in the new model, the number 43... no way that would work.)
However, I am getting a NullReferenceException error on this line:
DataTable testDataSymbols = codebook.Apply(testDt);
Here is the error:
System.NullReferenceException: Object reference not set to an instance of an object.
at Accord.Statistics.Filters.Codification.ProcessFilter(DataTable data)
at Accord.Statistics.Filters.BaseFilter`1.Apply(DataTable data)
at Agent.Business.BayesianClassifier.Categorize(String[] categories, String testText)
The objects I am passing in are all not null, so this must be something happening deeper in the code. But I am not sure what.
Thanks for any help. And if anyone knows of an example where a prediction is actually made from the bayesian example for Accord.Net, I would be much obliged if you shared it.

Sorry about the lack of documentation on the final part. In order to obtain the same integer codification for a new word, you could use the Translate method of the codebook:
// Compute the result for a sunny, cool, humid and windy day:
double[] input = codebook.Translate("Sunny", "Cool", "High", "Strong").ToDouble();
int answer = target.Compute(input);
string result = codebook.Translate("PlayTennis", answer); // result should be "no"
but it should also have been possible to call codebook.Apply to apply the same transformation to a new dataset. If you feel this is a bug, would you like to fill a bug report in the issue tracker?

Which approach to templating in C# should I take?

What I have
I have templates that are stored in a database, and JSON data that gets converted into a dictionary in C#.
Example: 
Template: "Hi {FirstName}"
Data: "{FirstName: 'Jack'}"
This works easily with one level of data by using a regular expression to pull out anything within {} in the template.
What I want
I would like to be able to go deeper in the JSON than the first layer.
Example:
Template: "Hi {Name: {First}}"
Data: "{Name: {First: 'Jack', Last: 'Smith'}}"
What approach should I be taking? (and some guidance on where to start with your pick)
A regular expression
Not use JSON in the template (in favor of xslt or something similar)
Something else
I'd also like to be able to loop through data in the template, but I have no idea at all where to start with that one!
Thanks heaps

You are in luck! SmartFormat does exactly as you describe. It is a lightweight, open-source string formatting utility.
It supports named placeholders:
var template = " {Name:{Last}, {First}} ";
var data = new { Name = new { First="Dwight", Last="Schrute" } };
var result = Smart.Format(template, data);
// Outputs: " Schrute, Dwight " SURPRISE!
It also supports list formatting:
var template = " {People:{}|, |, and} ";
var data = new { People = new[]{ "Dwight", "Michael", "Jim", "Pam" } };
var result = Smart.Format(template, data);
// Outputs: " Dwight, Michael, Jim, and Pam "
You can check out the unit tests for Named Placeholders and List Formatter to see plenty more examples!
It even has several forms of error-handling (ignore errors, output errors, throw errors).
Note: the named placeholder feature uses reflection and/or dictionary lookups, so you can deserialize the JSON into C# objects or nested Dictionaries, and it will work great!

Here is how I would do it:
Change your template to this format Hi {Name.First}
Now create a JavaScriptSerializer to convert JSON in Dictionary<string, object>
JavaScriptSerializer jss = new JavaScriptSerializer();
dynamic d = jss.Deserialize(data, typeof(object));
Now the variable d has the values of your JSON in a dictionary.
Having that you can run your template against a regex to replace {X.Y.Z.N} with the keys of the dictionary, recursively.
Full Example:
public void Test()
{
// Your template is simpler
string template = "Hi {Name.First}";
// some JSON
string data = #"{""Name"":{""First"":""Jack"",""Last"":""Smith""}}";
JavaScriptSerializer jss = new JavaScriptSerializer();
// now `d` contains all the values you need, in a dictionary
dynamic d = jss.Deserialize(data, typeof(object));
// running your template against a regex to
// extract the tokens that need to be replaced
var result = Regex.Replace(template, #"{?{([^}]+)}?}", (m) =>
{
// Skip escape values (ex: {{escaped value}} )
if (m.Value.StartsWith("{{"))
return m.Value;
// split the token by `.` to run against the dictionary
var pieces = m.Groups[1].Value.Split('.');
dynamic value = d;
// go after all the pieces, recursively going inside
// ex: "Name.First"
// Step 1 (value = value["Name"])
// value = new Dictionary<string, object>
// {
// { "First": "Jack" }, { "Last": "Smith" }
// };
// Step 2 (value = value["First"])
// value = "Jack"
foreach (var piece in pieces)
{
value = value[piece]; // go inside each time
}
return value;
});
}
I didn't handle exceptions (e.g. the value couldn't be found), you can handle this case and return the matched value if it wasn't found. m.Value for the raw value or m.Groups[1].Value for the string between {}.

Have you thought of using Javascript as your scripting language? I had great success with Jint, although the startup cost is high. Another option is Jurassic, which I haven't used myself.
If you happen to have a Web Application, using Razor maybe an idea, see here.
Using Regex or any sort of string parsing can certainly work for trivial things, but can get painful when you want logic or even just basic hierarchies. If you deserialize your JSON into nested Dictionaries, you can build a parser relatively easily:
// Untested and error prone, just to illustrate the concept
var parts = "parentObj.childObj.property".split('.');
Dictionary<object,object> current = yourDeserializedObject;
foreach(var key in parts.Take(parts.Length-1)){
current = current[key];
}
var value = current[parts.Last()];
Just whatever you do, don't do XSLT. Really, if XSLT is the answer then the question must have been really desperate :)

Why not us nvelocity or something?