I have a Data class which I populate manually from a XML returned from a trading Partner. Most of time the returned Data will only have a few of the fields in my class populated, the others I set to Nothing(null) and then use the
Dim settings As New JsonSerializerSettings
settings.NullValueHandling = NullValueHandling.Ignore
to suppress any field with no data. All that works great but I am wondering how I can do the same or similar for List of Objects in my class. Right now if there is no data for one of these I still get an an output like this which is an empty json Array.
{
"Txnum": "APO100000007R",
"Dtsent": "20180625105938",
"Txtyp": "A",
"Location": [],
"Terminationdata": [],
"Responsestatus": {
"prespc": "FTRAVQ059",
"prespd": "LV1 IS REQUIRED "
}
}
So I am wondering if and how I could avoid this short of checking json string before I return it and strip the "Location": [], for example.
This is the code that worked for me. Just as a Side Node the ShouldSerialize"PropertyName:() is case sensitive so ShouldSerializeLocation() works while ShouldSerializelocation() does not. In Vb code normally is not case sensitive so just watch for that to save your self some headache.
<XmlElement([Namespace]:=SynchronossNS)>
Public Property Location() As List(Of location)
Get
Return _location
End Get
Set
_location = Value
End Set
End Property
Public Function ShouldSerializeLocation() As Boolean
Return _location.Count > 0
End Function
Related
I have a JSON like this:
[
{
"areas": [
{
"area": "New York",
"isDay": true,
"temp": "14"
},
{
"area": "Washington DC",
"isDay": true,
"temp": "30"
},
{
"area": "Los Angles",
"isDay": false,
"temp": "54"
},
{
"area": "San Diego",
"isDay": true,
"temp": "59"
}
],
"status": true,
"code": 200,
"created_at": "2019/06/18 22:26:34.475",
"request_time": "2019/06/18 22:25:28.306"
}
]
I'm trying to get the value of the the area value on the first/second/third object under the Areas array.
I've tried this code to get the value of the first area of the array, which in this case is "New York".
'Note that 'rawJSON' is a string variable that contains the JSON.
Dim jResults As JObject = JObject.Parse(rawJSON)
Dim naming As String = jResults("areas")("name")
However when I run this, I get and exception:
Newtonsoft.Json.JsonReaderException: 'Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path '', line 1, position 1.'
I am trying to write a function that imports all 'areas' in each array with their identifier of area (such as New York/Washington DC) into a ListBox (so the ListBox will contain, in order: New York, Washington DC, Los Angles).
How can I do this?
There are a couple of problems here:
Your JSON begins and ends with square brackets, so that means it is an array, not a single object. Since it is an array you need to use JArray.Parse() to parse it instead of JObject.Parse().
Inside your array, there is a single object which contains a property areas along with a few other properties like status and code. The value of the areas property is also an array, as denoted by square brackets. So your code needs to account for both of those arrays by adding the indexes. If you want the first item, that would be index zero.
There is no property called name anywhere in the JSON you posted. Instead, the names of the cities are each in a property called area.
Putting it all together, if you want to get the name New York from this JSON, you would do it like this:
Dim jResults As JArray = JArray.Parse(rawJSON)
Dim name As String = jResults(0)("areas")(0)("area")
Demo: https://dotnetfiddle.net/eAfEsx
If you're trying to get multiple names, then you would need a loop. You could do something like this:
Dim names As New List(Of String)()
For Each area As JObject In jResults(0)("areas")
Dim name As String = area("area")
names.Add(name)
Next
Demo: https://dotnetfiddle.net/BtSa6O
As you can see from the JSON structure you have posted, the JSON starts with a square bracket. That's the start of an array, the StartArray: when the JsonReader starts reading the JSON, the first TokenType is a JsonToken.StartArray (what the error is telling you).
Then there's an Object, defined by the braces: { }.
So you have an Array or List of Objects.
The first property of this object (areas) is of Type Array (or List).
It defines a collection of Objects.
Other properties, (status, code, etc.) have a single value.
[
{
"areas": [ { ... }, { ... } ]
"other": "other value"
}
]
You can parse the outer Array with JArray. The first element in the array (and the only one you're showing here), is the outer array. The first property of the first element in the outer array is the areas Array.
So you could write:
Dim areasArray = JArray.Parse(rawJson)(0)("areas")
Dim firstAreaValue = areasArray(0)("area").ToString()
The value of firstAreaValue is then "New York".
This is can be tiresome and prone to errors. You can generate a class Model from the JSON and use this model to deserialize the JSON to .Net classes, making it easier to handle, use as Source of Data, modify, serialize back etc.
Your JSON is an Array of Objects, so let's build the Root Object as a .Net class:
Note that I've set the Type of the CreatedAt and RequestTime properties to DateTime (Date): the string format of the DateTime, "2019/06/18 22:26:34.475", can be deserialized correctly.
DateTimeOffset is probably better. Your choice.
Public Class AreasRoot
<JsonProperty("areas")>
Public Property Areas As List(Of AreaObject)
<JsonProperty("status")>
Public Property Status As Boolean
<JsonProperty("code")>
Public Property Code As Long
<JsonProperty("created_at")>
Public Property CreatedAt As DateTime
<JsonProperty("request_time")>
Public Property RequestTime As DateTime
End Class
The Areas property is an Array or List of another type of object that contains 3 properties:
Public Class AreaObject
<JsonProperty("area")>
Public Property AreaArea As String
<JsonProperty("isDay")>
Public Property IsDay As Boolean
<JsonProperty("temp")>
Public Property Temp As Long
End Class
To deserialize using this Model, call JsonConvert.DeserializeObject(Of Type)(json).
The Type is, as mentioned, an Array or List(Of RootObject):
Dim areasArray = JsonConvert.DeserializeObject(Of List(Of AreasRoot))(rawJson).First()
Now New York is:
Dim firstArea = areasArray.Areas.First().Area
' Or
Dim firstArea = areasArray.Areas(0).Area
You can list all the Area names with:
For Each areaObj In areasArray.Areas
Console.WriteLine(areaObj.Area)
Next
This is my first dealing with JSON and unfortunately I have to do it in VB.Net, company policy. So I have searched high and low and tried a lot of examples even converted some of the C# code to VB.Net but I can't seem to find a complete solution.
I receive a JSON string like this:
{
"65080007":{
"partNo":"ATD000007",
"description":"Swingarm Hat Platform",
"quantity":4,
"assemblyseq":""
},
"65080143":{
"partNo":"ATD000143",
"description":"ASY Gas Spring Bracket",
"quantity":2,
"assemblyseq":""
},
"65080071":{
"partNo":"ATD000071",
"description":"TT Gas Spring",
"quantity":2,
"assemblyseq":""
},
"65080147":{
"partNo":"ATD000147",
"description":"ASY Lateral Hinge",
"quantity":8,
"assemblyseq":""
},
"65085181":{
"partNo":"RD0181",
"description":"ASY KIT Bolt, Carriage, 0.375 in x 16, 1.5 in (x45) & Nut, Flange, 0.375 in x 16 (x45)",
"quantity":1,
"assemblyseq":""
},
"65080796":{
"partNo":"ATD000796",
"description":"Decal, TT Equipped, Rectangular, 5 in x 10 in",
"quantity":1,
"assemblyseq":""
},
"65080797":{
"partNo":"ATD000797",
"description":"Decal, TT Open/Close, Triangular, 12 in x 8 in",
"quantity":1,
"assemblyseq":""
},
"65080745":{
"partNo":"ATD000745",
"description":"",
"quantity":1,
"assemblyseq":""
}
}
What I need to do bind or assign this data to a DataGridView.DataSource.
I've seen some examples but I can't set it as a DataSource.
I've tried this example:
Sub Main()
Dim json_result = GetJson()
Dim table = JsonConvert.DeserializeAnonymousType(json_result, (DataTable))
Dim newJString = Newtonsoft.Json.JsonConvert.SerializeObject(table, Newtonsoft.Json.Formatting.Indented)
Console.WriteLine("Re-serialized JSON: ")
Console.WriteLine(newJString)
Console.WriteLine("")
End Sub
Public Function GetJson() As String
Dim json_result As String = <![CDATA[
' I used the above json string
Return json_result
End Function
I have made my JSON classes to deserialise the JSON and tried JsonConvert.Deserialize keep getting an error it epected a array and found an object.
Public Class Jobs
'<JsonProperty("partno")>
Public Property PartNo As String
' <JsonProperty("description")>
Public Property Description As String
'<JsonProperty("quantity")>
Public Property Quantity As String
'<JsonProperty("assemblyseq")>
Public Property Assemblyseq As String
End Class
The issue I think is the root properties "65080797" these numbers will not be the same every time we get the JSON back from NetSuite.
So I tried to:
Dim obj = JsonConvert.DeserializeObject(Of Jobs)(result)
Console.WriteLine(obj.PartNo) it comes out PartNo = nothing
So I've tried this:
Dim resultA = JsonUtil.Deserialize(Of Jobs)(result, ignoreRoot:=True)
Module JsonUtil
Function Deserialize(Of T As Class)(ByVal json As String, ByVal ignoreRoot As Boolean) As T
Return If(ignoreRoot, JObject.Parse(json)?.Properties()?.First()?.Value?.ToObject(Of T)(), JObject.Parse(json)?.ToObject(Of T)())
End Function
End Module
This gives me the first group:
ATD000007
Swingarm Hat Platform
4
The assembly number was blank.
I'm open for any suggestions on how I can get the above JSON into a data table or DataGridView or how to make a list without the root "65080797" this number will be unique with every response.
The people that designed this response string refuses to remove the root properties.
Thank you for taking the time to read this mess.
All comments/suggestions are appreciated.
Yes, Json array looks like [something] instead of {somthing}, you could convert it to array if you want but you can also do it in different ways and even without any external library, you could create a datatable then bind it to datagridview or you could add data directly to datagridview.
Anyway, I made a datatable for you.
Imports System.Web.Script.Serialization 'for reading of JSON (+add the reference to System.Web.Extensions library)
Dim JSONC = New JavaScriptSerializer().Deserialize(Of Dictionary(Of String, Dictionary(Of String, String)))(JSON) 'you could do it in different ways too
Dim NewDT As New DataTable
'Create Columns
For Each key In JSONC.First.Value.Keys
'"65080007" <first
'{ "partNo":"ATD000007", "description":"Swingarm Hat Platform", "quantity":4, "assemblyseq":"" } <first.value
' "partNo" <first.value.key(s) :"ATD000007" <first.value.value(s)
NewDT.Columns.Add(key)
Next
'Add Rows
For Each item In JSONC
NewDT.Rows.Add(item.Value.Values.ToArray)
Next
DataGridView1.DataSource = NewDT
If you have unusually structured JSON like that, your best bet is probably to resort to using raw JObject and JToken handling instead of trying to get JSON.NET to deserialize into structured data automatically.
Create a method that will convert an individual JToken into the Job class you described in your question. I've added a Key property to identify those unique keys in the JSON that were problematic for you; if you don't need these, just remove the .Key bit from the example below.
Public Function CreateJob(data As JToken)
Return New Job With
{
.Key = data.Path,
.PartNo = data("partNo"),
.Description = data("description"),
.Quantity = data("quantity"),
.Assemblyseq = data("assemblyseq")
}
End Function
Once you have Job objects being created, you can walk the entire structure and turn it into an array of jobs with the sample code below.
Dim result As JObject = JsonConvert.DeserializeObject(json)
Dim jobs As Job() = result.Values().Select(Of Job)(AddressOf CreateJob).ToArray()
Once you have an array of Job objects, binding to a DataSource should be trivial.
I am making an application in vb net, and read JSON format files.
I know how, but I have a file that has a different format, you can see here:
{
"objects": {
"realms/lang/de_DE.lang": {
"hash": "729b2c09d5c588787b23127eeda2730f9c039194",
"size": 7784
},
"realms/lang/cy_GB.lang": {
"hash": "7b52463b2df4685d2d82c5d257fd5ec79843d618",
"size": 7688
},
"minecraft/sounds/mob/blaze/breathe4.ogg": {
"hash": "78d544a240d627005aaef6033fd646eafc66fe7a",
"size": 22054
},
"minecraft/sounds/dig/sand4.ogg": {
"hash": "37afa06f97d58767a1cd1382386db878be1532dd",
"size": 5491
}
}
}
It is different because all text has objects, no string, so I can not read it defined classes.
I just need the values of "hash", then add them to a textbox.
I hope you can help me.
Sounds like #Plutonix has seen this before, so I'll go with the Minecraft thing. It seems like objects is a Dictionary(Of String, MinecraftItem). A little tweak to the linked duplicate could be to create a class for the whole file, so you don't have to pull out the objects separately:
Public Class MinecraftData
Public Property Objects As Dictionary(Of String, MinecraftItem)
End Class
Public Class MinecraftItem
Public Property Hash As String
Public Property Size As Long
End Class
You can then parse the whole thing using Json.NET:
Dim data = JsonConvert.DeserializeObject(Of MinecraftData)(json)
If you are certain that you will only ever need the hashes, you can actually use a regex to get all the hashes from this file. Yes, this is slightly evil, because regex is normally not a suitable tool for dealing with structured data. But if you don't care about the structure...
Dim hashExtractor = new System.Text.RegularExpressions.Regex("[0-9a-f]{40}")
Dim matches = hashExtractor.Matches(myFileContents).Cast(of System.Text.RegularExpressions.Match)
Dim hashes = matches.Select(Function(m) m.Value).ToList()
JObject.Parse(jsonString) is causing issue for boolean data. e.g. The json is :
{
"BoolParam": true
}
I used the following code to parse:
JObject data = JObject.Parse(str1);
foreach (var x in data)
{
string name = x.Key;
Console.Write(name + " (");
JToken value = x.Value;
Console.Write(value.Type + ")\n");
Console.WriteLine(value);
}
This print out the value as :
BoolParam (Boolean) : True
The case sensitivity causes issue as I save this json for later use. The saved json looks like
{
"BoolParam": True
}
However, when i later use it, the JObject.Parse(str) throws error as invalid Json :Unexpected character encountered while parsing value: T. Path 'BoolParam', line 2, position 15.
If I change the case from "True" to "true", it works. I dont want to add this hack to change the case when saving but is there a better way to handle this scenario.
I dont want to add this hack to change the case when saving but is
there a better way to handle this scenario.
No, you have to produce valid JSON when saving if you want to be able to later deserialize it with a JSON serializer such as Newtonsoft JSON. So fixing your saving routing is the right way to go here.
One could use anonymous types and no worry about case sensitivity of boolean type variables
public static void Main()
{
bool a = true;
JObject c = JObject.FromObject(new {BoolParam= a});
Console.WriteLine(c);
}
Output:
{
"BoolParam": true
}
I have a web api endpoint that receives JSON and serializes it into objects. Very basic and common stuff. However, I have a requirement to accept custom user defined fields. For example, a developer may want to add a custom field for "account #" and pass that along via the API. I'm stuck how I could define a field on my class if I don't know the name. I need to support unlimited fields so I cannot simply create a field for custom1, custom2, custom2, etc.
I would think that my JSON could look something like this... where custom_label_xxx is identifies the field label:
...
"custom_fields": {
"custom_label_90": 49,
"custom_label_83": [ 28, 29, 30 ],
"custom_label_89": "2012/05/21"
},
...
How in the world can I setup a dynamic class to accept this dynamic JSON?
I have Googled forever and cannot find any examples using custom fields.
Your post method can accept dynamic as a param:
public HttpResponseMessage Post(dynamic obj)
This will accept every json that you send.
Saykor's reply is probably correct. However, I already have tons of business objects to work with and I only wanted the custom fields to be dynamic. Also, I wanted the Web API Help pages to be generated with sample JSON. So making the method dynamic would not work well for me.
What I finally did was probably obvious to some. I created a property on the class that was a dictionary. When I run the Help Pages it generates sample JSON that looks exactly what I needed. I have not tested this yet, but I assume it will serialize the JSON into a dictionary.
Here is the property in VB, but it could easily use dynamic in C# as well.
Private _customfields As Dictionary(Of String, String)
<DataMember(EmitDefaultValue:=False, IsRequired:=False, Order:=11)> _
Public Property customfields() As Dictionary(Of String, String)
Get
Return Me._customfields
End Get
Set(ByVal value As Dictionary(Of String, String))
Me._customfields = value
End Set
End Property
This resulted in the following JSON:
"customfields": {
"sample string 1": "sample string 2",
"sample string 3": "sample string 4",
"sample string 5": "sample string 6"
}