I have the following string (json format)
I have gotten from my server:
{[{"ruta": "1","division": "7"},{"ruta": "2","division": "7"},{"ruta": "3","division":"7"},{"ruta": "4","division": "7"},{"ruta": "5","division": "7"},{"ruta": "23","division": "7"}]}
I want to get each value and save them in string variables in order to save them in a data base.
For that I am trying to do as follows:
JArray jarr = JArray.Parse(result);
foreach (JObject content in jarr.Children<JObject>())
{
foreach (JProperty prop in content.Properties())
{
string tempValue = prop.Value.ToString; // This is not allowed
//here more code in order to save in a database
}
}
But I can't find the way to convert the values to string.
Use ToString(), not ToString.
ToString() is a method call; ToString is a reference to the ToString method, and can only be assigned to a compatible delegate.
You can also cast to String, since the JToken class defines a conversion:
string tempValue = (string)prop.Value;
Another option to consider is to use JSON serialization: create a class that represents the JSON data (with the same structure), and deserialize the JSON to this class. It makes the code much more readable and maintainable.
You can directly de serialize your json using C# class(using:- http://json2csharp.com/) and not need to iterate through Json.
public class YourClass
{
public string ruta { get; set; }
public string division { get; set; }
}
You can de serialize
List<YourClass> yourClasslist= JsonConvert.DeserializeObject<List<YourClass>>(result.ToString());
You can do this because your Json is in structured format
JArray jarr = JArray.Parse(result);
foreach (JObject content in jarr.Children<JObject>())
{
foreach (JProperty prop in content.Properties())
{
string tempValue = prop.Value.ToString(); // This is not allowed
//here more code in order to save in a database
}
}
as for the JSON you should start from a JObject since it's surrounded by { }, or remove them from around the JSON you posted in your question
JProperty.Value is of type JToken which has a method ToString (and not a property).
See documentation here.
The syntax should be like that:
string tempValue = prop.Value.ToString();
Related
I want to convert something like this this {\"ref\":\"/my/path\",\"action\":\"set\",\"payload\":\"\"}
into a generic object in C#. What i tried is this
object mess1 = JObject.Parse(message);
dynamic mess2 = JsonConvert.DeserializeObject<object>(message);
dynamic mess3 = JValue.Parse(message);
The expected result would be an object with the properties ref, action and set. The actual result is an object containing the JObject
ChildrenTokens
Count
First
HasValues
Last
Next
Parent
...
these are not part of my object. What is the correct way of doing this?
The payload in this message is a string OR an arbitrary object. The payload is to be written to a database and i do not care what it contains.
JObject.Parse generates a JObject instance. You can do this a couple of ways, if you already have JObject, you can do the following:
var obj = JObject.Parse(json);
var command = obj.ToObject<Command>();
Or, you can work from the string:
var command = JsonConvert.Deserialize<Command>(json);
We generally use
this method
public static JObject JsonParsed(string Json)
{
return JObject.Parse(Json);
}
You can deserialize it into a dynamic object with:
dynamic parsed = JObject.Parse("ref\":\"/my/path\",\"action\":\"set\",\"payload\":\"\");
And access your properties like any other object:
Console.WriteLine(parsed.ref); // "/my/path/"
Console.WriteLine(parsed.action); // "set"
Console.WriteLine(parsed.payload); // "\"
By "object with my properties" you mean what's often referred as POCO.
You have to define a POCO object like so:
public class Poco
{
public string Ref { get; set; }
public string Action { get; set; }
public string Payload { get; set; }
}
Then deserialize your JSON like so:
string json = "{'ref':'/my/path','action':'set','payload':''}";
Poco myPoco = JsonConvert.DeserializeObject<Poco>(json);
Now you will have myPoco.Ref, myPoco.Action, myPoco.Payload properties populated from your JSON.
I have this json string, which contains two elements each with a Number and a Status:
var jsonString = "{\"Errors\":[{\"Number\":9,\"Status\":\"BadRequest\"}, {\"Number\":3,\"Status\":\"BadConnection\"}]}";
As you see it has a parent property called Errors.
I have prepared this model:
public class ExceptionStructure
{
public int Number { get; set; }
public string Status { get; set; }
}
Using NewtonSoft.Json I would like to deserialize the json string into an array of ExceptionStructure objects, without also having to create a model for the parent property (as I don't really need it).
Can I do this (perhaps with some json attribute on the model class)?
I was hoping to do something like this to deserialize:
var exceptionArr = JsonConvert.DeserializeObject<ExceptionStructure>(jsonString);
JSON.NET allows you to deserialize parts of a json file. You can do this by first deserialzing the json string to a JObject, extract the relevant parts, and then deserialize those to your actual object.
JObject errors = JObject.Parse(jsonString);
IList<JToken> results = errors["Errors"].Children().ToList();
IList<ExceptionStructure> exceptions = new List<ExceptionStructure>();
foreach (JToken result in results)
{
ExceptionStructure exception= result.ToObject<ExceptionStructure>();
exceptions.Add(exception);
}
Honestly though, in your case it might be easier to just build a Errors parent class
More information can be found at http://www.newtonsoft.com/json/help/html/SerializingJSONFragments.htm
this is may be helpful you.
string s = "{\"Errors\":[{\"Number\":9,\"Status\":\"BadRequest\"}, {\"Number\":3,\"Status\":\"BadConnection\"}]}";
var jobj = JObject.Parse(s);
List<ExceptionStructure> list = jobj["Errors"].ToObject<List<ExceptionStructure>>();
OR:
string s = "{\"Errors\":[{\"Number\":9,\"Status\":\"BadRequest\"}, {\"Number\":3,\"Status\":\"BadConnection\"}]}";
List<ExceptionStructure> list = JObject.Parse(s)
.SelectToken("Errors")
.ToObject<List<ExceptionStructure>>();
I have the following raw JSON string:
[\"Hello World!\",\"94952923696694934\",\"MyChannel\"]
I have tried the following without luck:
My custom object class:
public class MyObject
{
public string msg { get; set; }
public string id { get; set; }
public string chn { get; set; }
}
JSON string:
string str = "[\"Hello World!\",\"94952923696694934\",\"MyChannel\"]";
1st attempt at deserilization using System.Web.Script.Serialization:
JavaScriptSerializer serializer = new JavaScriptSerializer();
MyObject obj1 = serializer.Deserialize<MyObject>(str);
2nd attempt at deserilization using Newtonsoft.Json:
MyObject obj2 = JsonConvert.DeserializeObject<MyObject>(str);
Both attempts fail. Any suggestions?
You have a JSON array of strings, not an object with property names.
So the best you can do here is to deserialize the array:
IEnumerable<string> strings =
JsonConvert.DeserializeObject<IEnumerable<string>>(str);
...then use the resulting sequence strings as you see fit.
With PubNub, you can just pass in the native String, Dictionary, or Array, and we'll JSON encode it for you on the publish side, and auto JSON decode for you on the subscriber side.
It's because your 'custom object' isn't equivalent to the json representation. The json you're deserializing is just a string[] in C# (you can also use List<string> or other IEums).
So in code you're looking for;
string[] theJson = JsonConvert.DeserializeObject<string[]>(str);
MyObject would be used for the following json;
{
"msg":"Hello World!",
"id":"94952923696694934",
"chn":"MyChannel"
}
I am trying to read json from a local .json file and parse the contents using StreamReader and Json.NET. Json & my code:
contents of .json file: {"rate":50,"information":{"height":70,"ssn":43,"name":"andrew"}}
using (var sr = new StreamReader(pathToJsonFile))
{
dynamic jsonArray = JsonConvert.DeserializeObject(sr.ReadToEnd());
foreach(var item in jsonArray)
{
Console.WriteLine(item.rate);
Console.WriteLine(item.ssn);
}
}
This gives me an error on the line foreach(var item in array): Object reference not set to an instance of an object. I am guessing this is because my json is not actually an array but that is how I am trying to parse it. How can I parse this json in order to pull out fields such as rate or ssn?
NB - please do not flag this question as a duplicate of Read and parse a Json File in C#, as that is where I got my original code from.
EDIT: As has been pointed out in other answers, jsonArray is null. That explains my error but still does not answer my question. How else can I parse this json in order to extract the desired fields?
A couple things:
If you want to manually parse out the values, you should try using JObject rather than JsonConvert.DeserializeObject. The following code should work:
dynamic jsonObject = JObject.Parse("{'rate':50,'information':{'height':70,'ssn':43,'name':'andrew'}}");
Console.WriteLine(jsonObject["rate"]);
Console.WriteLine(jsonObject["information"]["ssn"]);
However, if you know how the json is structured, you should create a .net class like:
public class Person
{
public int rate {get;set;}
public Information information {get;set;}
}
public class Information
{
public int height {get;set;}
public int ssn {get;set;}
public string name {get;set;}
}
and then use:
var person = JsonConvert.DeserializeObject<Person>(thestringtodeserialize);
That way you can have a strongly typed object.
In any case, I would check for null (DeserializeObject can obviously return null):
using (var sr = new StreamReader(pathToJsonFile))
{
dynamic jsonArray = JsonConvert.DeserializeObject(sr.ReadToEnd());
if(jsonArray != null) //new check here
{
foreach(var item in jsonArray)
{
Console.WriteLine(item.rate);
Console.WriteLine(item.ssn);
}
}
I am guessing this is because my json is not actually an array
True, the returned object is dynamic, so make use of dynamic:
var json = "{\"rate\":50,\"information\":{\"height\":70,\"ssn\":43,\"name\":\"andrew\"}}";
dynamic obj = JsonConvert.DeserializeObject(json);
Console.WriteLine("rate: {0}. ssn: {1}", obj.rate, obj.information.ssn);
See live sample here: https://dotnetfiddle.net/nQYuyX
Are you sure it's an array?
If that's the format the you expect from Json, maybe you should consider defining a class.
For example:
class SomeJsonObject
{
public int rate {get;set;}
[JsonProperty("information")] //if you want to name your property something else
public InformationObject Information {get;set;}
}
class InformationObject
{
[JsonProperty("height", NullValueHandling = NullValueHandling.Ignore)] //some other things you can do with Json
public int Height {get;set;}
public int ssn {get;set;}
public string name {get;set;}
}
This way you can just deserialize it to an object:
SomeJsonObject jsonArray = JsonConvert.DeserializeObject<SomeJsonObject>(sr.ReadToEnd());
I think your question is similar to this Deserialize JSON with C# . you can use JavaScriptSerializer
I don't get a null reference (with Json.net 6.0.3) but your code has one obvious bug:
static void Main(string[] args)
{
string s = "{'rate':50,'information':{'height':70,'ssn':43,'name':'andrew'}}".Replace('\'', '\"');
var obj = JsonConvert.DeserializeObject(s);
dynamic jsonArray = obj;
foreach (var item in jsonArray)
{
Console.WriteLine(item.rate);
Console.WriteLine(item.ssn);
}
}
The bug is Console.WriteLine(item.rate) will throw.
Your 'array' jsonArray is not actually an array, it is a dictionary!
Therefore, item=the first Key-Value-pair in the dictionary, = {"rate":50}.
You can prevent the code from throwing by getting rid of your foreach loop.
i would fire up nuget and get the JSON.net package
https://www.nuget.org/packages/Newtonsoft.Json/
http://james.newtonking.com/json
it is well documented and can save you a tonne of work.
see also http://json2csharp.com/
EDIT: you are already using this
I'm recieving a JSON object that looks like the example below.
{
"name1":{"name1a":"value1a","name1b":"value1b"},
"name2":{"name2a":"value2a","name2b":"value2b"}
}
I've set up a data contract for it (since I only need to access a single data field at the moment) like this.
[DataContract]
public class MyThingy
{
[DataMember(Name="name1b")]
public string Name1b { get; set; }
public MyThingy() { }
public MyThingy(String name1b)
{
Name1b = name1b;
}
}
When I've serialized the object, I try to print it out (which works, since I'm getting a string description of the class) and them the field Name1b. The last part doesn't work and I'm getting null there. My guess is that I must have mapped the data contract wrongly but I can't see how to correct it.
How should the MyThingy class be declared?
My JSON object is fetched as described in this post.
I would use JavaScriptSerializer here,
string json = #"{
""name1"":{""name1a"":""value1a"",""name1b"":""value1b""},
""name2"":{""name2a"":""value2a"",""name2b"":""value2b""}
}";
var obj = new JavaScriptSerializer()
.Deserialize<Dictionary<string, Dictionary<string, string>>>(json);
Console.WriteLine(obj["name1"]["name1b"]);
You can also use Json.Net and dynamic together
dynamic obj = JsonConvert.DeserializeObject(json);
Console.WriteLine(obj.name1.name1b);