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Custom JSON field names with Newtonsoft as defined by a variable [duplicate]

I have a method which accepts a key and a value. Both variables can have a dynamic content.
key => is a dynamic string which can be everything like e.g. "LastSentDate"
value => is an object which can be everything like e.g. "2014-10-10"
As key is a dynamic value like "LastSentDate" or whatever key is passed to the method then I want that the json property is the value of the key string and not literally key itself...
public void SetRowVariable(string key, object value)
{
var obj = new { key = value }; // key property is literally taken maybe anonym object is not a good idea?
string jsonString = JsonConvert.SerializeObject(obj);
// jsonString should have that output => "{ "LastSentDate": "2014-10-10" }"
}
How do I have to serialize the obj that I get the wished output?
It must also be possible that the "key" property can contain special chars like "!"§$%&/()=?"`
I am using .NET 3.5 sadly.

You could use a JObject (in Newtonsoft.Json.Linq):
var obj = new JObject();
obj[key] = JToken.FromObject(value);
string jsonString = obj.ToString();

You may try using a Dictionary<string, object>:
public void SetRowVariable(string key, object value)
{
var obj = new Dictionary<string, object>();
obj[key] = value; // Of course you can put whatever crap you want here as long as your keys are unique
string jsonString = JsonConvert.SerializeObject(obj);
...
}

Get properties from dynamic object using startswith

I want to get all properties from json that StartsWith particular text
dynamic results = JsonConvert.DeserializeObject<dynamic>(json);
So now below is what i get in results
{"abc" : "Text", "abcde" : "Text2","prop" : "myprop"}
Is it possible to do something like
results.Where(x => x.StartsWith("abc"))

You could simply use results.GetType().GetProperties(), which will give you an array of properties present in the deserialized JSON object.
You could then iterate over that array to get the PropertyInfo objects whose Name starts with whatever string you want, and call GetValue() to obtain the properties' values of interest.
Or you simply don't deserialize at all, but parse the object and treat it as JSON:
var jObject = JObject.Parse(jsonString);
foreach (var rootProperty in jObject)
{
if (rootProperty.Key.StartsWith("whatever"))
{
var valueOfInterest = rootProperty.Value;
}
}

Simply retrieve the runtime-type of the result-object and query its properties using Type.GetProperties:
var type = results.GetType();
type.GetProperties().Where(x => x.Name.StartsWith("abc"));
EDIT: Because any method called on an instance of dynamic is dynamic as well, you have to cast the result of results.GetType into Type. Otherwise you´ll get a compiler-err stating that you can´t use an anonymous method on a dynamically bound operation.
var type = (Type)results.GetType();

Deserialize JSON string into class with reflection

I'm trying to deserialize a JSON string into a custom class. I have to use reflection. I have a dictionary that I serialize, send over to an HttpPut method, deserialize the JSON string, and read the dictionary fields. Here's what I have so far:
I'm putting values into the Dictionary like this:
Dictionary<string, object> valuesToUpdate = new Dictionary<string, object>();
Person p = new Person();
p.personName = "OrigName";
p.age = "25";
p.isAlive = true;
valuesToUpdate.Add("Person", p);
valuesToUpdate.Add("Length", 64.0);
I'm using JSON to serialize it like this:
string jsonString = JsonConvert.SerializeObject(valuesToUpdate);
I then take the jsonString and send it over to a REST API PUT method. The PUT method updates various variables on a custom object based on the Key values in the dictionary using reflection (In this example I'm updating customObject.Person and customObject.Length).
The PUT call deserializes the jsonString like this:
Dictionary<string, object> newFields = JsonConvert.DeserializeObject<Dictionary<string, object>>(jsonString);
I iterate through newFields and want to use reflection to update customObject's "Person" class. This is my HttpPut method that reads the jsonString:
[HttpPut("/test/stuff")]
public string PutContact([FromBody]dynamic jsonString)
{
Dictionary<string, object> newFields = JsonConvert.DeserializeObject<Dictionary<string, object>>(jsonString);
foreach (var field in newFields)
{
Console.WriteLine("\nField key: " + field.Key);
Console.WriteLine("Field value: " + field.Value + "\n");
PropertyInfo propInfo = typeof(Contact).GetProperty(field.Key);
Type propertyType = propInfo.PropertyType;
var value = propInfo.GetValue(contactToUpdate, null);
if (propertyType.IsClass)
{
propInfo.SetValue(contactToUpdate, field.Value, null);
}
}
}
This generates the error:
Object of type Newtonsoft.Json.Linq.JObject' cannot be converted to type 'Person';
I've also tried using JSON's PopulateObject method but it returned this error:
Newtonsoft.Json.JsonSerializationException: Cannot populate JSON object onto type 'Person'. Path 'personName', line 1....
So basically, how can you go about taking a JSON string, converting it to a class (in my case the 'Person' class), and setting it to customObject's Person field with reflection?

if (propertyType.IsClass)
{
propInfo.SetValue(contactToUpdate, ((JObject)field.Value).ToObject(propertyType), null);
}

Dictionary<string, object> how I can take the object value

I have the method
HandleNotification(string message, Dictionary<string, object> additionalData, bool isActive)
and I would take the from additionalData the value.
I have this additional data:
Extracoins:4
I don't understand how I can take the value 4 from additionalData for a specific key Extracoins.

You can get a value from a Dictionary like this if your only interested in accessing one specific key.
object value = null;
additionalData.TryGetValue("Extracoins", out value);
That way object will be the value in the Dictionary or it will remain null if the value is not found.
Or you can do:
if (additionalData.ContainsKey("Extracoins"))
{
object value = additionalData["Extracoins"];
}
Finally if you wanted to iterate over all the values in the Dictionary until you get the correct value you could do:
object value = null;
foreach (KeyValuePair<string, object> pair in additionalData)
{
if (pair.Key == "Extracoins")
{
value = pair.Value;
}
}

Can a PSObject have properties that are PSObjects?

I have a C# Cmdlet that interacts with a REST service, deserializing JSON as dynamic objects (ExpandoObject). When an expando is passed to WriteObject it gets written to the pipeline as a dictionary so I am converting it to a PSObject like so in order to make its properties accessible by the likes of Select-Object:
protected void WriteDynamicObject(dynamic o)
{
var psObject = ConvertToPSObject(o);
WriteObject(psObject);
}
private static PSObject ConvertToPSObject(dynamic o)
{
var d = o as IDictionary<string, object>;
Debug.Assert(d != null);
var record = new PSObject();
foreach (var kvp in d)
{
// if the value is itself an expando, convert it recursively
var value = kvp.Value is ExpandoObject ? ConvertToPSObject(kvp.Value) : kvp.Value;
record.Properties.Add(new PSNoteProperty(kvp.Key, value));
}
return record;
}
This works swimmingly for all of the dynamic object's properties except for properties that are themselves a complex type. The above code will recursively convert non-scalar child objects into PSObject instances. As an example the projectTeam property of this JSON result is converted to a PSOBject:
{
"kind": "storage#bucketAccessControl",
"role": "OWNER",
"projectTeam": {
"projectNumber": "930617506804",
"team": "owners"
},
"etag": "CAE="
}
When I try to select the projectTeam property from the pipeline I get a string representation and cannot select the properties of that sub object:
projectTeam
-----------
#{projectNumber=930617506804; team=owners}
#{projectNumber=930617506804; team=editors}
#{projectNumber=930617506804; team=viewers}
I guess I was expecting to be able to select or otherwise navigate the object hierarchy. Are PSObjects intended to be essentially a flat set of name value pairs or can they represent an object hierarchy? If so, how does one represent a nested object such that its properties are selectable or is it necessary to flatten the object hierarchy?