Develop Reference

C# web API property object as string not object

I have an web API function that has a property that can take different shapes. Actually i need to save a json in database.
I will give you some examples
post body
{
"title":"example 1",
"type": "0",
"extraData": { "name": "bob",
// here is the catch this is first type of object let's say children
[{
"age": 10
"toys": "bear, goat"
},
{
"age": 18
"toys": "guitar"
}]
}
}
{
"title":"example 1",
"type": "1",
"extraData": { "name": "john",
// here is the catch this is first type of object let's say grandparents
[{
"age": 90
"cars": "honda civic"
},
{
"age": 18
"car": "renault megan, pegeout 206"
}]
}
}
Now let's assume that we can't merge grandparents and children together in a class so my classes will look something like:
public class Family{
public string Title {get; set;}
public string ExtraData {get; set;}
public int Type {get;set;}
}
public class ExtraData<T> where T: Person{
public string Name{get;set;}
public List<T> Persons {get;set;}
}
public class Person{
public int Age {get;set;}
}
public class Child : Person{
public string Toys{get;set;}
}
public class Grandparent : Person{
public string Cars{get;set;}
}
In the api method I was thinking to do something like:
public void Save(Family model)
{
// to parse extraData my idea was to
switch(mode.Type)
{
case 0: var childrens = JsonConvert.DeserializeObject<ExtraData<Child>>(model.ExtraData);
// do stuff
break;
case 1: var grandparents = JsonConvert.DeserializeObject<ExtraData<Child>>(model.ExtraData);
// do stuff
break;
}
// save the object
}
The issue is that on the api call I get nothing in the extraData string. And I can't put in Family something like
public ExtraData<Person> Persons {get;set;}
because it will deserialize to the base type and I will lose the subclass information.
I know is to do something like json stringify but I would like this to be my last resort. Also i have tried to use dynamic instead of Family but I still need to deserialze it and having same issue.
What is the best approach here?

Avoid serialization of a property name in json.net

How to avoid a property name during serialization? Below an example
public class A {
public List<object> Values { get; set; }
public string Name { get; set; }
}
A a = new A();
a.Name = "Numbers"
a.Values = new List<object>();
a.Values.Add(1);
a.Values.Add(2);
a.Values.Add(3);
a.Values.Add(4);
JsonConvert.SerializeObject(new { a });
After serialization, result includes a property names "values"
{
"a": {
"values": [
1,
2,
3,
4
],
"name": "Numbers"
}
}
but, I need the following
{
"a": [
1,
2,
3,
4
],
"name": "Numbers"
}

Just serialize a.Values;
JsonConvert.SerializeObject(a.Values);

You have a couple mistakes in your code.
First, if you want this class:
public class A
{
public List<object> Values { get; set; }
public string Name { get; set; }
}
To serialize to this json:
{
"a": [
1,
2,
3,
4
],
"name": "Numbers"
}
You are gonna have a bad time. Just look at the structure, they are not 1-1.
You need to change your class, make sure you name it something meaningful (a class of a single letter is a really bad idea).
public class SomeClass
{
[JsonProperty("a")]
public List<object> Values { get; set; }
[JsonProperty("name")]
public string Name { get; set; }
}
You notice the [JsonProperty()] attribute above? That tells the serializer that this property should serialize with the defined name. That way you can have a meaningful property name ("Values") while in code, and still have the json serialize the way you want it to ("a").
The second problem is when you serialize you are creating a new anonymous object with a property of the class you instance you created. Which will again mess your structure up. Change your serialization code to just serialize the object instance:
string json = JsonConvert.SerializeObject(someInstanceOfYourClass);
My above changes should give you json that looks like this:
{
"a": [
1,
2,
3,
4
],
"name": "Numbers"
}
I have made a fiddle here that will demonstrate.

How to store C# objects with dynamic properties in RavenDB?

I'm having problems when trying to save an object that has a dynamic property in RavenDB
The object I'm trying to save represents an order. The order contains a list of orderlines so imagine the following Order class:
public class Order {
public int Id { get; set; }
public List<Orderline> Orderlines { get; set; }
}
And the Orderline class being:
public class Orderline {
public Product Product { get; set; }
public int Quantity { get; set; }
public dynamic Attributes { get; set; }
}
The object I'm trying to save (I'll display it with JSON);
{
"Id": 0,
"Orderlines": [
{
"Product": {
"Id": 0,
"Name": "Some product"
},
"Quantity": 1,
"Attributes": {
"color": "Red"
}
}
]
}
Saving it does not throw any errors
RavenDB stores the Order object as
{
"Id": 0,
"Orderlines": [
{
"Product": {
"Id": 0,
"Name": "Some product"
},
"Quantity": 1,
"Attributes": {
"$type": "Newtonsoft.Json.Linq.JObject, Newtonsoft.Json",
"color": {
"$type": "Newtonsoft.Json.Linq.JValue, Newtonsoft.Json",
"$values": []
}
}
}
]
}
Note that the values property of Order.Orderlines[0].Attributes.color is not set...
When I try to serialize the object back to my C# Order object I get the following exception;
Unable to cast object of type
'Raven.Imports.Newtonsoft.Json.Utilities.CollectionWrapper`1[Newtonsoft.Json.Linq.JToken]'
to type 'Newtonsoft.Json.Linq.JValue'.
What am I doing wrong, how can I store this object in the RavenDB database and retrieve it?

What is the type that you are actually saving into attributes?
Typically you'll use something that is actually dynamic, like ExpandoObject

Storing the dynamic property with type 'dynamic' apparently wasn't enough. When I gave the Attributes property the ExpandoObject type, RavenDB stored the Attributes property as normal JSON (without $type and $values, so clean as desired)
When retrieving it back from the RavenDB database it deserializes back to an ExpandoObject object.
Make sure to cast the ExpandoObject property to a dynamic (e.g. 'as dynamic') when trying to display the property in a Razor view.

Finding a column value where columnID equals xxxx in JSON using C#

I am using C# to grab values from a JSON file and put them into a database. I am new to JSON and so don't really know too much of how to work with it. I will do my best to explain the structure I have and what I am trying to do. But to sum up I am trying to call a variable from JSON in a similar way you would do in an SQL Where statement. So grab this value where this other value = x.
So the JSON format is as follows.
Firstly it idenfitifies the columns.
"columns": [
{
"id": 8098453499733892,
"index": 0,
"title": "Task Name",
"type": "TEXT_NUMBER",
"format": ",,,,,,2,,,,,,,,,1",
"primary": true,
"width": 378
},
{
"id": 780104105256836,
"index": 1,
"title": "KPI (RYG)",
"type": "PICKLIST",
"symbol": "RYG",
"options": [
"Red",
"Yellow",
"Green"
],.....
Then the rows and cells within that:
"id": 2157159933863812,
"rowNumber": 2,
"parentRowNumber": 1,
"parentId": 7786659468076932,
"expanded": false,
"format": ",,1,,,,,,,22,,,,,,",
"createdAt": "2015-03-04T15:58:28+13:00",
"modifiedAt": "2015-03-04T15:58:32+13:00",
"cells": [
{
"columnId": 8098453499733892,
"type": "TEXT_NUMBER",
"value": "GLH Toll MASTER FROM WEEK 47",
"displayValue": "GLH Toll MASTER FROM WEEK 47",
"format": ",,1,,,,2,,,22,,,,,,1"
},
{
"columnId": 2750428942231428,
"type": "CHECKBOX",
"value": true,
"format": ",,1,,,,,,,22,,,,,,"
},
Ok so for an example. What I want to do is grab the columnID value in the cell, and then use that to find the title value in the column. So in the above example, I would want to find 'title' where id in column equals 8098453499733892, which would give me the result of 'Task Name'.
I don't even know if this is possible but have struggled to find a working example on the web. FYI I am using smartsheets.

You need to create an equivalent object/class in your c# containing those properties in your JSON. In order to get the columnID column based on your JSON structure, you need to create the the class below:
class Class1 {
public string id { get; set; }
public int rowNumber { get; set; }
public int parentId { get; set; }
public bool expanded { get; set; }
public string format{ get; set; }
public List <Cells> cells {get; set;}
}
class Cells {
public string columnId {get; set;}
public string type{get; set;}
public bool value{get; set;}
public string format {get; set;}
}
You need to deserialize the JSON string from the API using the Class1 object and from there you can access whatever column that you need.

For anyone looking I used the where clause in the select token. Here is the code that I used to find the column title based on an id value.
var test = jObject.SelectToken("columns").Where(t => t["id"].Value<Int64>() == 5283703732627332).FirstOrDefault()["title"].Value<string>();

Hiding C# properties when serialize with JSON.NET

How can we hide the C# property where serializing with JSON.NET library. Suppose, we have class Customer
public class Customer
{
public int CustId {get; set;}
public string FirstName {get; set;}
public string LastName {get; set;}
public bool isLocked {get; set;}
public Customer() {}
}
public class Test
{
Customer cust = new Customer();
cust.CustId = 101;
cust.FirstName = "John"
cust.LastName = "Murphy"
string Json = JsonConvert.SerializeObject(cust);
}
JSON
{
"CustId": 101,
"FirstName": "John",
"LastName": "Murphy",
"isLocked": false
}
This object is converted to json, but i didn't specify the isLocked property. As library will serialize the entire class, is there any way to ignore a property during json serialization process or if we can add any attribute on the property.
EDIT:
Also, If we create two instance of Customer class in an array. if we didn't specify is locked property on the second instance, can we can property hide for second object.
JSON
{
"Customer": [
{
"CustId": 101,
"FirstName": "John",
"LastName": "Murphy",
"isLocked": false
},
{
"CustId": 102,
"FirstName": "Sara",
"LastName": "connie"
}
]
}

Use the JSON.Net attributes:
public class Customer
{
public int CustId {get; set;}
public string FirstName {get; set;}
public string LastName {get; set;}
[JsonIgnore]
public bool isLocked {get; set;}
public Customer() {}
}
For more information: https://www.newtonsoft.com/json/help/html/SerializationAttributes.htm

Yes, marking your properties with JsonIgnore is probably best.
However, if you do want to chose at runtime, add a public bool ShouldSerialize{MemberName} to your class. When JSON.net Serialises it will call it, and if false, not serialise. isLocked is false by default, perhaps you do want to serialise it when its true, for example.

Mark that property with the JsonIgnore attribute.