json string to dictionary.

General
1

I have a string with json in it.
I want to convert it to a json object and then to a dictionary.
Help?

2

The new framework can do this for you if you’re interested in that: http://developer.xojo.com/xojo-data$ParseJSON

4

http://documentation.xojo.com/index.php/JSONItem.Constructor(JSONString_as_String)
You then manipulate the data as if it were a dictionary…

It seems the old framework would allow you to create a JSONItem from a Dictionary, so perhaps you could do the reverse?

5

Dim dict As Xojo.Core.Dictionary
dict = Xojo.Data.ParseJSON(content.ToText)

{“host”:“name.domain.local”,“source”:“heartbeat”,“event”:{“uptimeMs”:64414110,“lastBootTimeEpochMs”:1503361326865}}

Is raising the exception that the string must have known encoding…

6

That’s a goofy glitch with ToText.
I avoid it by defining the encoding on the string immediately before using ToText.

7

It’s not a glitch…

8

I recall that the default encoding for String is supposed to be UTF8. It’s also glitchy if you define the encoding and manipulate the string before trying to .ToText it.

9

Dim dict As Xojo.Core.Dictionary Dim aString As String = content.DefineEncoding(Encodings.UTF8) dict = Xojo.Data.ParseJSON(aString.ToText)

Just curious but is Dictionary and Dim dict As Xojo.Core.Dictionary interchangable?
i.e. can I pass an Xojo.Core.Dictionary to a method that is expecting a Dictionary?

10

For the most part, try to work in either the new framework or the old framework as most (all?) of the new classes are not toll-free to the old framework classes…

11

[code]dim d as dictionary 'old framework

dim d as xojo.core.dictionary 'new framework

using xojo.core
dim d as dictionary 'new framework[/code]

12

is there a place where the using statement belongs in a whole project?

Do I itterate through this object the exact same way as I do for the old dictionary?

13

Lots of sample code in the documentation, but some times finding the right thing is the hard part…

http://developer.xojo.com/xojo-core-dictionaryentry

Each DictionaryEntry in the loop has a .key and .value property…

14

In traversing the json one of the values itself could be another dictionary.

In the iterator how can you tell if the Value’s type is a xojo.Core.Dictionary and recurse?

Sub parse(d as Xojo.Core.Dictionary) For Each entry As Xojo.Core.DictionaryEntry In d if entry.value.isa(xojo.Core.Dictionary then // ? parse(entry.Value) end if Next End Sub

15

You can insert a using clause however the scope is private & unchangeable so it is only class or module wide.

16

how do I tell what the class of an object is?

// This is probably not valid… but do you know what I mean?
entry.value.isa(xojo.Core.Dictionary)

17

I didn’t test, but if (entry.value IsA Xojo.Core.Dictionary) then

18

The IsA line throws an type mismatch exception in the debugger, but clearly the object is a Xojo.Core.Dictionary.

[code]Function ToString(d as Xojo.Core.Dictionary, level as integer=0) As String
dim s as string=""
dim tabs as string=""
dim i as integer
dim entry as xojo.Core.DictionaryEntry

for i=0 to level-1
tabs = tabs + chr(9)
next

// Type Mismatch Exception Expected Object but got Int64
For Each entry In d
if entry.Value isa Xojo.Core.Dictionary then
s=s+ToString(entry.Value, level+1)
else
s = s + tabs + entry.Key + “=” + entry.Value + EndOfLine.UNIX
end if
Next

return s
End Function[/code]