Develop Reference

How to parse JSON with Newtonsoft?

I created an ASP.NET Application, where I have to parse a csv file with a json structure.
The csv file itself is structured like:
{"Instance":"abc","Date":"2019-06-03T00:00:02.056Z","Identification":"someFunction","Type":"DurationInMs","Value":"5","iserror":"False""}
I get the jsonCsvData as a string and tried to parse it. Then I want to save some of the elements of this json object into a db.
public IActionResult ReadJsonCsvData(string jsonCsvData)
{
Console.WriteLine("ReadJsonCsvData");
ChartData chartData = new ChartData();
var lines = jsonCsvData.Split("\n");
foreach (var line in lines)
{
var values = JObject.Parse(line);
var first = string.Concat(values["Instance"]); //Output for first: ""
}
}
The problem now is, that the variable first is an empty string. The result should be (like in the json structure example above) "abc".
Thank you in advance!

I don't know if it will help but here is my solution (remove one of " at the end of your Json).
I use the "Jobject" to parse Json as I want. Import this two reference.
using Newtonsoft.Json.Linq;
using Newtonsoft;
Then you have to create your JObject :
JObject o = JObject.Parse(myJsonString);
Then to retrieve specifics data, you just have to search in your object just like you do with a dictionary with key :
instanceFromJson = o["Instance"].ToString;
dateFromJson = o["Date"].ToString;
If you have a table in your "instance" json object you can retrieve all data from this list just like that :
foreach (var item in o["Instance"]["tabFromInstanceObject"])
{
MyList.Add(item);
}

Reading two Json Files and merging them in C#

I am trying to read 2 json files using StreamReader, parse them as JObjects and then perform a merge. However I have am receiving the following error when StreamReader is called for the second time:
Error reading JObject from JsonReader. Current JsonReader item is not
an object: StartArray. Path '', line 1, position 1.
For the line:
string jsonUpdateFile = updatesr.ReadToEnd();
The code below:
var path = String.Format("{0}json\\data.json", AppDomain.CurrentDomain.BaseDirectory);
string jsonOldFile = new StreamReader(path).ReadToEnd();
var updatepath = String.Format("{0}json\\update.json", AppDomain.CurrentDomain.BaseDirectory);
string jsonUpdateFile = new StreamReader(updatepath).ReadToEnd();
var jsonO = JObject.Parse(jsonOldFile);
var jsonU = JObject.Parse(jsonUpdateFile);
//merge new json into old json
jsonO.Merge(jsonU);
//save to file
FileInfo file = new FileInfo(path);
file.Directory.Create();
string JsonToSave = JsonConvert.SerializeObject(jsonO);
System.IO.File.WriteAllText(#path, JsonToSave);
What I am trying to do with the merge:
var jsonO = [{"id":"1234","name":"Bruce"},{"id":"5678","name":"Clark"}]
var jsonU = [{"id":"1234","name":"Wayne"}]
var merge = [{"id":"1234","name":"Wayne"},{"id":"5678","name":"Clark"}

You can take JArray and add the second Json to First One i.e, Like this one
var jsonO = JArray.Parse(jsonOldFile);
var jsonU = JArray.Parse(jsonUpdateFile);
foreach(JObject innerData in jsonU )
{
jsonO.Add(innerData);
}
In order to Update the other json I think you can try this one i dont know once give it a shot
var jsonO = JArray.Parse(jsonOldFile);
var jsonU = JArray.Parse(jsonUpdateFile);
var item = jsonO.Children<JObject>();
foreach(JObject innerData in jsonU)
{
if(innerData[Id] == item[Id])
{
item[Name] = innerData[Name];
jsonO.Replace(item["Name"]);
//[or]
jsonO.Add(item["Name"});
}
else
{
jsonO.Add(innerData);
}
}
even i'm a newbie if i'm wrong please do correct me happy to learn it ..

var jsonO = JArray.Parse(jsonOldFile);
var jsonU = JArray.Parse(jsonUpdateFile);
Using JArray rather than JObject allows me to read the files in. Merge doesn't work as expected but that's a question for another thread.

By looking at the error stated in question, my guess is that your update.json file is not in a valid json format. Please use http://jsonlint.com/ to validate your json first.

Parsing JSON in c# return null value

I am trying to Parse Json in C# . (I am beginner in Json)
WebRequest webRequest = WebRequest.Create(url);
var httpWebRequest = (HttpWebRequest)webRequest;
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
String responseText = "";
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
responseText = streamReader.ReadToEnd();
}
//
This is Output in responseText :
{
"disclaimer": "Exchange rates provided for informational purposes only and do not constitute financial advice of any kind. Although every attempt is made to ensure quality, no guarantees are made of accuracy, validity, availability, or fitness for any purpose. All usage subject to acceptance of Terms: https://openexchangerates.org/terms/",
"license": "Data sourced from various providers; resale prohibited; no warranties given of any kind. All usage subject to License Agreement: https://openexchangerates.org/license/",
"timestamp": 1454497211,
"base": "EUR",
"rates": {
"INR": 74.42686146,
"USD": 1.0929332
}
}
To get the base from Json
var obj = JObject.Parse(responseText);
String bcur = (string)obj["base"];
Console.WriteLine("base :"bcur.ToString());
Output : base :EUR
similarly to get Rates of INR , I wrote
var obj = JObject.Parse(responseText);
String rte= (string)obj["INR"];
Console.WriteLine("rate:"rte);
it gives me null.
Can anyone tell me what is wrong in my code. or a better way to get the base and rate of the currency .

INR is not in the base object, so you are looking for the INR property in a place where it doesn't exist. You would have to go about it in a two step fashion in order to access the property in . Modifiying your code above, it would look something like this:
var obj = JObject.Parse(responseText);
JObject rates = (JObject)obj["rates"];
string rte = (string)rates["INR"];
Console.WriteLine("rate:" + rte);

json add new object to existing json file C#

I'm trying to automate the addition of new objects to an existing JSON file. I looked all around the web but only found adding data and stuff but not a whole object. This is how the file that I want to edit looks:
[
{"id":"123","name":"carl"}
]
and I want to go to
[
{"id":"123","name":"carl"},
{"id":"1234","name":"carl2"}
]
Thank you for all your answers but I don't think everyone completely understands what i mean I have tried some of the answers but then I get this:
[
"{\"id\":\"123\",\"name\":\"carl\"}"
]"{\"id\":\"1234\",\"name\":\"carl2\"}"
and I want everything in between the [].

If you use json.NET you can simply deserialize and serialize the json.
var list = JsonConvert.DeserializeObject<List<Person>>(myJsonString);
list.Add(new Person(1234,"carl2");
var convertedJson = JsonConvert.SerializeObject(list, Formatting.Indented);

Using Json.Net
//load from file
var initialJson = "[{\"id\":\"123\",\"name\":\"carl\"}]";
var array = JArray.Parse(initialJson);
var itemToAdd = new JObject();
itemToAdd["id"] = 1234;
itemToAdd["name"] = "carl2";
array.Add(itemToAdd);
var jsonToOutput = JsonConvert.SerializeObject(array, Formatting.Indented);
//save to file here
Using this method doesn't require strongly typed objects
You could replace this bit:
//load from file
var initialJson = "[{\"id\":\"123\",\"name\":\"carl\"}]";
With
var initialJson = File.ReadAllText(#"c:\myjson.json")
To load the json from a text file

A better performing solution than serializing/deserializing what may be a large file would be to open a FileStream, seek 1 character before the end, then serialize and write your new object into the array, then write a closing bracket. See this question C# How to delete last 2 characters from text file and write into the same line at the end my text?, I'll copy the code here - you already know how to serialize your object and encode it into bytes.
using(var fs = new FileStream("file.json")) {
fs.Seek(-1,SeekOrigin.End);
fs.Write(mySerializedJSONObjAsBytes,0,mySerializedJSONObjAsBytes.Length); // include a leading comma character if required
fs.Write(squareBracketByte, 0, 1);
fs.SetLength(fs.Position); //Only needed if new content may be smaller than old
}
Sorry haven't tested any of that, it's off the top of my head. Pro-tip: wrap FileStream in a StreamWriter so can write strings directly.

You could create a method:
public string AddObjectsToJson<T>(string json, List<T> objects)
{
List<T> list = JsonConvert.DeserializeObject<List<T>>(json);
list.AddRange(objects);
return JsonConvert.SerializeObject(list);
}
Then use it like this:
string baseJson = "[{\"id\":\"123\",\"name\":\"carl\"}]";
List<Person> personsToAdd = new List<Person>() { new Person(1234,"carl2") };
string updatedJson = AddObjectsToJson(baseJson, personsToAdd);

this would be a sample for you:
var list = JsonConvert.DeserializeObject<List<Example>>(json);
Example example = new Example();
example.name = "Product2";
example.id="1";
list.Add(example);
string output = JsonConvert.SerializeObject(list);
public class Example
{
public string id {get;set;}
public string name { get; set; }
}

I have been looking for a solution to this exact question for a week now. I finally figured out how to append it to the existing json array and not add it as a solo object after the array. Make sure you are using WriteAllText and not AppendAllText. Here is what I did:
JArray array = JsonConvert.DeserializeObject<JArray (jsonFile);
JObject obj = new JObject();
obj.Add("ID", "123");
obj.Add("Name", "Brian");
array.Add(obj);
var jsonToOutput = JsonConvert.SerializeObject(array, Formatting.Indented);
File.WriteAllText("fileName.json", jsonToOutput);

How to Parse Json data to normal data in C#

I am beginner in c#, I have output from the website like {"result":"Invalid"} with my c# program, It seems to be Json ,I want to display these data as normal string and display it in message box and use those parsed data for validation
Program:
private async void Button_Click(object sender, RoutedEventArgs e)
{
var username = Username.Text;
var password = passbox .Password;
var postMessage = new StringContent(string.Format("username={0}&password={1}", username, password), Encoding.UTF8 , "application/x-www-form-urlencoded");
var response = await (new HttpClient()).PostAsync("http://xxx.xx.net/xx.php", postMessage);
var responseBody = await response.Content.ReadAsStringAsync();
MessageBox.Show( responseBody );
}
I want to know how to display the responseBody as normal string ?

Ideal solution depends on how complex Json string you got. If it has only single property-value pair like posted in question :
{"result":"Invalid"}
I think simple string manipulation logic will bring you the value ("Invalid") easily. Like this naive code :
var jsonString = "{\"result\":\"Invalid\"}";
//remove "{" and "}" from sting
var result = jsonString.Replace("{", "").Replace("}", "");
//separate property name from it's value
var pair = result.Split(':');
//property will contain property name : "result"
var property = pair[0];
//value will contain property value : "Invalid"
var value = pair[1];
Otherwise, if JSON response is more complex, it is not reliable to use string manipulation. I'd suggest to go with Newtonsoft.Json library as also suggested by #Mohammad.

Try using JSON.Net using below code if it returns result as output then
string json = responseBody;
JObject parsed = JObject.Parse(json);
string results = (string)parsed["result"];

Not too sure if this is the best approach... But I'm currently implementing something similar, and using a reader to... read the returned data.
System.IO.StreamReader reader = new System.IO.StreamReader(response.GetResponseStream());
string outputStr = reader.ReadToEnd();

To convert JSON object to string you should serialize it.
I'm using Newtonsoft.Json
After install above package you can use it as the following :
string jsonInString = JsonConvert.SerializeObject(responseBody);
MessageBox.Show(jsonInString);
And for convert json string to an object you can use the following :
ClassName obj = JsonConvert.DeserializeObject<ClassName>(jsonInString);