MY JSON String
{
"name": "username",
"status": "mystatus",
"place": {
"name": "placename",
}
My Code
Dim request As HttpWebRequest
Dim response As HttpWebResponse = Nothing
Dim reader As StreamReader
Try
request = DirectCast(WebRequest.Create("http://myjsonstring.com/json"), HttpWebRequest)
response = DirectCast(request.GetResponse(), HttpWebResponse)
reader = New StreamReader(response.GetResponseStream())
Dim rawresp As String
rawresp = reader.ReadToEnd()
Dim jResults As JObject = JObject.Parse(rawresp)
if (rawresp != null)
name.Text = jResults("name").ToString()
status.Text = jResults("status").ToString()
placename.Text = jResults("place")("name").ToString()
End If
Catch ex As System.Net.WebException
MsgBox(ex.ToString)
Finally
If Not response Is Nothing Then response.Close()
End Try
my issue is sometimes my json may look like this
{
"name": "username",
"place": {
"name": "placename",
}
My JSON Explained
"name": "name here",
"items": {
"myitem": {
"icon": "myitem.jpg",
"myitem2": {
"icon": "myitem2.jpg",
}
My Code I Have Tried
myitem.Text = If(jResults2("items")("myitem")("icon") Is Nothing, "", jResults2("items")("myitem")("icon").ToString())
myitem2.Text = If(jResults2("items")("myitem2")("icon") Is Nothing, "", jResults2("items")("myitem2")("icon").ToString())
when the value is missing from myitem it stops the JSON and myitem2 never displays.
As this happens my project throws a null value exception, I have severely condensed my json string and code for readability but my question is there a way to handle the error when "status" is missing from the string and continue to parse the rest of the objects?
Or if its possible when this value is missing/null replace it with something else but if this route was chosen I would like to set a different value for each.
Check if jResults("status") and other properties are null (Nothing) before doing .ToString().
Dim jResults As JObject = JObject.Parse(rawresp)
name.Text = If(jResults("name") Is Nothing, "", jResults("name").ToString())
status.Text = If(jResults("status") Is Nothing, "", jResults("status").ToString())
placename.Text = If(jResults("place") Is Nothing, "", jResults("place")("name").ToString())
Related
I have this Json data need to get the values on vb.net
{
"type": "push",
"targets": ["stream"],
"push": {
"type": "mirror",
"source_device_iden": "ujzp6Xr9A4asjyjskXPzu8",
"source_user_iden": "ujzp6Xr9A4a",
"client_version": 354,
"dismissible": true,
"icon": "ok",
"title": "test",
"body": "Hi",
"application_name": "WhatsApp",
"package_name": "com.whatsapp",
"notification_id": "1",
"notification_tag": "y9x5Q2YAI\/pqPhZwbaN6TpoW4eJhe0kAe0HfmWOQyWA=\n",
"conversation_iden": "{\"package_name\":\"com.whatsapp\",\"tag\":\"y9x5Q2YAI\\\/pqPhZwbaN6TpoW4eJhe0kAe0HfmWOQyWA=\\n\",\"id\":1}"
}
}
I tried this code it is return error
Dim json As String = TextBox1.Text
Dim ser As JObject = JObject.Parse(json)
Dim data As List(Of JToken) = ser.Children().ToList
For Each item As JProperty In data
item.CreateReader()
Select Case item.Name
Case "push"
For Each msg As JObject In item.Value
Dim tyep As String = msg("type")
Dim source As String = msg("source_device_iden")
Next
End Select
Next
System.InvalidCastException: 'Unable to cast object of type
'Newtonsoft.Json.Linq.JProperty' to type
'Newtonsoft.Json.Linq.JObject'.'
Dim json As String = TextBox1.Text
Dim ser As JObject = JObject.Parse(json)
Dim data As List(Of JToken) = ser.Children().ToList
For Each item As JProperty In data
item.CreateReader()
Select Case item.Name
Case "push"
For Each msg As JObject In item
Dim tyep As String = msg("type")
Dim source As String = msg("source_device_iden")
Next
End Select
Next
JsonObjectBuilder builder = factory.createObjectBuilder().add("input", input);
JsonObject jsonData = builder.build();
String jsonDataString = jsonData.toString();
try {
OutputStream jsonStream = new FileOutputStream(jsonPath);
OutputStreamWriter jsonStreamWriter = new OutputStreamWriter(jsonStream);
Gson gson = new GsonBuilder().setPrettyPrinting().create();
String prettyOutput = gson.toJson(jsonData);
System.out.println(prettyOutput);
jsonStreamWriter.write(prettyOutput);
}
catch(Exception e) {}
The output I get is weird:
It adds '"value":' before every string value of a key.
My JSON data is something like this:
{
"input": {
"record0": {
"Active": "",
"Level": "",
"Name": "Pre-Session",
"Description": "",
"Record": "",
"Field": "",
"Std. Rule": "",
"Ext. Rule": "//Updated By: Sukanya Dasgupta On: 25-Jan-2016"
}
}
}
Not an expect but I think the problem is that public String toJson(Object src) loses type information :
This method should be used when the specified object is not a generic
type. This method uses Object.getClass() to get the type for the
specified object, but the getClass() loses the generic type
information because of the Type Erasure feature of Java.
I'm trying to read URL containing JSON
Reading the file in the URL is ok, but when trying to parse the JSON I get an error:
An unhandled exception of type 'Newtonsoft.Json.JsonReaderException' occurred in Newtonsoft.Json.dll
Additional information: Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path '', line 2, position 2.
The code:
Dim request As HttpWebRequest
Dim response As HttpWebResponse = Nothing
Dim reader As StreamReader
request = DirectCast(WebRequest.Create("http://phvarde.kundeside.dk/json?key=t6%$SVAKsG39"), HttpWebRequest)
response = DirectCast(request.GetResponse(), HttpWebResponse)
reader = New StreamReader(response.GetResponseStream())
Dim rawresp As String
rawresp = reader.ReadToEnd()
Dim jResults As Object = JObject.Parse(rawresp)
TxtFornavn.Text = If(jResults("name") Is Nothing, "", jResults("name").ToString())
TxtAdresse.Text = If(jResults("address") Is Nothing, "", jResults("address").ToString())
You are getting this error because your JSON represents an array of objects, not just a single object. In this case you need to use JArray.Parse instead of JObject.Parse.
Dim array As JArray = JArray.Parse(json)
For Each item As JObject In array
Dim name As String = If(item("name") Is Nothing, "", item("name").ToString())
Dim address As String = If(item("address") Is Nothing, "", item("address").ToString())
// ... process name and address ...
Next
Fiddle: https://dotnetfiddle.net/2wfA17
Dim url As String = String.Format("{0}folders/{1}", boxApiUrl, ParentFolderId) 'ParentFolderId being pass is "0"
Using request = New HttpRequestMessage() With {.RequestUri = New Uri(url), .Method = HttpMethod.Post}
request.Headers.Authorization = New System.Net.Http.Headers.AuthenticationHeaderValue("Authorization", "Bearer " + acctoken)
Dim data As Dictionary(Of [String], [String]) = New Dictionary(Of String, String)()
data.Add("name", FolderName)
Dim content As HttpContent = New FormUrlEncodedContent(data)
request.Content = content
Dim response = _httpClient.SendAsync(request).Result
If response.IsSuccessStatusCode Then
'
End If
End Using
My suspicion is that data is not being put together properly but can't figure out how else to pass folder name to be created under the root. All other functions (reading root folder, uploading file, etc.) using the token works fine.
The parent folder ID is passed in the POST body, not the URL. The body should be JSON data in the form: { "name": "FolderName", "parent": { "id": "ParentFolderId" }}. Documentation.
Dim url As String = String.Format("{0}folders", boxApiUrl)
Using request = New HttpRequestMessage() With {.RequestUri = New Uri(url), .Method = HttpMethod.Post}
request.Headers.Authorization = New System.Net.Http.Headers.AuthenticationHeaderValue("Authorization", "Bearer " + acctoken)
Dim format as String = #"{{ ""name"":""{0}"", ""parent"": {{ ""id"":""{1}"" }} }}";
Dim body as String = String.Format(format, FolderName, ParentFolderId);
request.Content = New StringContent(body, Encoding.UTF8, "application/json")
Dim response = _httpClient.SendAsync(request).Result
If response.IsSuccessStatusCode Then
'
End If
End Using
As an aside, you can use Json.NET's JsonConvert.SerializeObject method to serialize an anonymous or static type to a JSON string:
Dim obj = New With {Key .name = FolderName,
.parent = New With {Key .id = ParentFolderId }};
Dim body as String = JsonConvert.SerializeObject(body);
request.Content = New StringContent(body, Encoding.UTF8, "application/json")
I have a problem with Newtonsoft.Json. I'm trying to parse JSON from a URL but I'm getting an error. Here is the JSON:
[
{
"ID": "0",
"Nome": "we",
"Data": "2013-09-16",
"Orario": "00:00:16",
"Prestazione": "dfg",
"Stato": "dfg",
"Numero_Telefono": "dfg"
},
{
"ID": "0",
"Nome": "fg",
"Data": "2013-09-26",
"Orario": "00:00:00",
"Prestazione": "",
"Stato": "",
"Numero_Telefono": ""
},
{
"ID": "1",
"Nome": "davide",
"Data": "2013-09-26",
"Orario": "00:00:16",
"Prestazione": "ds",
"Stato": "sd",
"Numero_Telefono": "3546"
}
]
Here is the code I am using:
Dim request As HttpWebRequest
Dim response As HttpWebResponse = Nothing
Dim reader As StreamReader
Try
request = DirectCast(WebRequest.Create("http://nhd.altervista.org/connectDb.php"), HttpWebRequest)
response = DirectCast(request.GetResponse(), HttpWebResponse)
reader = New StreamReader(response.GetResponseStream())
Dim rawresp As String
rawresp = reader.ReadToEnd()
Dim jResults As JObject = JObject.Parse(rawresp)
Dim results As List(Of JToken) = jResults.Children().ToList()
For Each item As JProperty In results
item.CreateReader()
MsgBox(item.Value("img")) ' because my tag in json is img
Next
Catch ex As Exception
Console.WriteLine(ex.ToString)
MsgBox(ex.ToString)
Finally
If Not response Is Nothing Then response.Close()
End Try
This is the error I receive when I try to parse the JSON:
Newtonsoft.Json.JsonReaderException: Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path '', line 1, position 1.
Can you help me solve this?
You are getting this error because you are using JObject.Parse, which expects a single JSON object, but your JSON contains an array. To correct this, use JArray.Parse instead.
But, there is another problem: the rest of your code is not set up to handle the results correctly. Because your results are an array of objects, your For Each loop needs to be expecting JObject items, not JProperty items. Once you have each item, you can then get the properties from them as needed.
I am not sure what you were trying to do with the item.CreateReader() line, as you are not doing anything with its return value, and you don't seem to need anyway. Similarly, I am also confused with your MsgBox(item.Value("img")) line, because there is no "img" property anywhere in the JSON. So this will always be null.
Here is some corrected code which will parse the JSON and display all the properties for each object in the results. This should give you a starting point to work with.
Dim request As HttpWebRequest
Dim response As HttpWebResponse = Nothing
Dim reader As StreamReader
Try
request = DirectCast(WebRequest.Create("http://nhd.altervista.org/connectDb.php"), HttpWebRequest)
response = DirectCast(request.GetResponse(), HttpWebResponse)
reader = New StreamReader(response.GetResponseStream())
Dim rawresp As String
rawresp = reader.ReadToEnd()
Dim jResults As JArray = JArray.Parse(rawresp)
Dim results As List(Of JToken) = jResults.Children().ToList()
For Each item As JObject In results
Dim demo As String = ""
For Each prop As JProperty In item.Properties()
demo = demo + prop.Name + " = " + prop.Value.ToString() + vbCrLf
Next
MsgBox(demo)
Next
Catch ex As Exception
Console.WriteLine(ex.ToString)
MsgBox(ex.ToString)
Finally
If Not response Is Nothing Then response.Close()
End Try