I tried using Newtonsoft.Json to deserialize this json string, but I'm not getting the desired output.
my json string is
[
{
"id": 1,
"key": "Residential Homeowner",
"i18nText": "unknown message code DB_ENUM_UserType_residentialhomeowner",
"i18nKey": "DB_ENUM_UserType_residentialhomeowner"
},
{
"id": 8,
"key": "VAR Dealer \/ Builder",
"i18nText": "unknown message code DB_ENUM_UserType_vardealer\/builder",
"i18nKey": "DB_ENUM_UserType_vardealer\/builder"
},
{
"id": 2,
"key": "Administrator",
"i18nText": "unknown message code DB_ENUM_UserType_administrator",
"i18nKey": "DB_ENUM_UserType_administrator"
},
{
"id": 9998,
"key": "TempGuidUser",
"i18nText": "unknown message code DB_ENUM_UserType_tempguiduser",
"i18nKey": "DB_ENUM_UserType_tempguiduser"
},
{
"id": 9999,
"key": "GuidUser",
"i18nText": "unknown message code DB_ENUM_UserType_guiduser",
"i18nKey": "DB_ENUM_UserType_guiduser"
}
]
I just want the value of key when value of id=1. Generally json starts with {}(curly bracket) but here it is like [](square bracket). I've seen many examples but none worked for me.
Generally json starts with {} (curly bracket), but here it is like [] (square bracket).
This is because you got an array of objects, not a single object. Arrays are serialized with square brackets around them. You should deserialize it into an array, and then grab the object at the index of interest.
This is a related post that addresses JSON parsing in C#: C# JSON Parsing.
If the brackets are a problem, simply use:
string json = inputJson.Trim().Trim('[',']');
If the id can have a minimum value of 1, then this should work:
string GetKey(string inputJson)
{
string key = inputJson.Substring(inputJson.IndexOf("key")+5);
key = key.Substring(key.IndexOf("\""), key.IndexOf(",")-key.IndexOf("\""));
key = key.Trim('\"');
return key;
}
If you are only interested in a single value from that larger JSON value, you may want to try Linq to JSON which would allow you to query over the JSON without deserializing everything.
Example:
JArray values = JArray.Parse(json);
string key;
var keyObject = values.FirstOrDefault(p => (int)p["id"] == 1);
if (keyObject != null)
{
key = (string)keyObject["key"];
}
[] is to define a json object array. Your output should be an array. Traverse through the array like:
for(var i=0; i<output.Length; i++)
{
if(output[i].id == "1") // desired id
{
Console.WriteLine(output[i].key);// use it as you wish
}
}
and use the found objects key.
Related
Expected result:
"sections": [
{
"sectionName": "Test Data",
"sectionOrder": 1,
"sectionColumn": 1
}
]
Actual Result:
"sections": [
{
"sectionName": [],
"sectionOrder": [],
"sectionColumn": []
}
]
I am assuming that the newtonsoft causes the issue for the datatype.
I'm serializing a section and returning JSON like:
var serializer = new JavaScriptSerializer();
var result = serializer.Serialize(testdata);
While debugging, it is showing integer value in the result for sectionOrder and sectionColumn but somehow the postman showing the result as empty array.
Not getting any exception in the result
postman result with empty array
enter image description here
This question already has answers here:
How can I deserialize JSON to a simple Dictionary<string,string> in ASP.NET?
(22 answers)
Closed 3 years ago.
I have a JSON similar to the following:
{
"type": "FeatureCollection",
"totalFeatures": "unknown",
"features": [
{
"type": "Feature",
"id": "xxx",
"geometry": {
"type": "MultiPolygon",
"coordinates": [
[
570389.865,
4722149.567
],
[
570389.865,
4722149.567
]
]
}
}
]
}
Is there a way to get the coordinates property of the first feature without using substring or parsing it to an class that represents that JSON?
I'm looking for something standard for handling JSON strings as an Object, with methods for getting childs by name or similar.
Any help would be appreciated
You can use Newtonsoft.Json library.
Here's example of getting coordinates field (using JSONPath):
var parsed = JObject.Parse(yourJson);
// returns JToken (but actually it's JArray, derived from JToken)
var coordArrayToken = parsed.SelectToken("$.features[0].geometry.coordinates");
var coordinates = coordArrayToken.ToObject<decimal[][]>();
Of course you can use simple indexers:
var parsed = JObject.Parse(yourJson);
// returns JToken (but actually it's JArray, derived from JToken)
var coordArrayToken = parsed["features"].Children().First()["geometry"]["coordinates"];
var coordinates = coordArrayToken.ToObject<decimal[][]>();
I'm trying to check if In the json there is a certain property. Actually I can do it in the following way:
var container = (JContainer)JsonConvert.DeserializeObject(responseText);
var x = container.ToString(Formatting.None);
var message = container["text"];
now the variable responseText is returned as:
{[
{
"trace": {
"details": {
"data": "[29-02-2016 17:37:32.931751]",
"type": "[info]",
"text": "[Done.]"
},
"context": {
"context": [
[
{
"ID": "John Dillinger"
}
]
]
}
}
}
]}
in the x variable I have removed the space and the final result is:
"[{\"trace\":{\"details\":{\"data\":\"[29-02-2016 17:37:32.931751]\",\"type\":\"[info]\",\"text\":\"[Done.]\"},\"context\":{\"context\":[[{\"ID\":\"John Dillinger\"}]]}}}]"
Now if the key isn't found I get null:
if (message == null)
{
return responseText;
}
the problem is that I perform the condition on the message variable that check if in the container (not formatted) there is the property, the problem is that I get this exception:
{"Accessed JArray values with invalid key value: \"text\". Int32 array index expected."}
but if I replace container with the second json with the slash all working good. Now my problem is that I can't execute var message= x["text"]; 'cause x is a string. So how I can remove the space in the json and check if contain the text key?
It looks like when you removed the space, you also changed the order of the first brackets In the first example your first brackets are {[, in the second they are [{
In json, the ordering makes a difference. {} means object and [] means array.
[{"data":"value"}] is legal because you are saying that you have an array of an object. {["value"]} is not legal because your object does not have a name for the array. The legal version would be { "data":["value"] }
Here is a handy web tool to verify your JSON syntax
I have a piece of JSON that I want to get into a string for C# to use. The problem is when I escape all the double quotes it seems no longer valid. For example:
string jsonString = " {[ { \"FieldId\": \"Fields.364\", \"FieldName\": \"LoanNo\", \"Precision\": \"0\" } , { \"FieldId\": \"Fields.4002\", \"FieldName\": \"LastNameB\" } ]}";
JObject jsettings = JObject.Parse(jsonString);
Is there a easier way to get a string of JSON into a C# JObject?
You're not actually escaping any of the double quotes, as far as the JSON is concerned - the string doesn't contain any backslashes. You can confirm that with Console.WriteLine(jsonString);.
The problem is that you've currently got an array directly inside an object - that's not valid JSON.
If you change it so that the array is a property, it's fine:
string jsonString = " { \"foo\":[ { /* rest as before */ } ] }";
That ended up as JSON of:
{
"foo": [
{
"FieldId": "Fields.364",
"FieldName": "LoanNo",
"Precision": "0"
},
{
"FieldId": "Fields.4002",
"FieldName": "LastNameB"
}
]
}
(Just using Console.WriteLine(jsettings); after the code you'd posted.)
I am using Json.NET 6.x and I noticed weird behaviour:
If I want to deserialize this simple JSON, I get an error:
The code to deserialize:
object o = Newtonsoft.Json.JsonConvert.DeserializeObject(text);
and the JSON:
[
{
"Username": "tb386",
"TimestampUpdated": "2015-01-19T18:49:52.771571+01:00",
"AuthTokens": [
"Ua7JR5E7hSAxjafp6dpMrvw3HlICW3ZZdDuArMaU5ks="
]
}
]
The error I get is:
Unexpected character encountered while parsing value: U. Path '', line 0, position 0.
If I remove the array, it works fine. But all I have to do, is to remove the string inside the array, making it empty:
[
{
"Username": "tb386",
"TimestampUpdated": "2015-01-19T18:49:52.771571+01:00",
"AuthTokens": [ ]
}
]
and then it works fine. I should also note that the serialized JSON was produced by the Newtonsoft library, so the source is the same library!
If I try a validator (like http://jsonlint.com/) on the JSON with the array, it valides OK!
Can anyone help me out here?
Additional information: Even if I add a string inside VS and write the JSON hardcoded, it fails!
string text = "[ {\"Username\": \"tb386\",\"TimestampUpdated\": \"2015-01-19T18:49:52.771571+01:00\",\"AuthTokens\": [\"Ua7JR5E7hSAxjafp6dpMrvw3HlICW3ZZdDuArMaU5ks=\"] } ]";
object o = Newtonsoft.Json.JsonConvert.DeserializeObject(text);
Version info on Newtonsoft dll: