Read & Write JSON file || Basics

[Chazrox]

Im learning how to build my own sub-menus and im running into a couple of things I need advice on.

I've learned how to use the minimal FileSystem api's that allow me to create a file and read from a file. Im only good for one liners only at this point. lol

1. How do I now create a JSON file filled with values,

2. How do I access them?

Anybody care to share a run down on this process please!

End goal:

Create an object with key value pairs ' name : "string" ' , call up the value based on the name in a combobox, and apply the value to a component.

[d.healey]

@Chazrox

// Create an object
const myObj = {"name": "Dave", "age": 38, "country": "England"};

// Save object to a file on desktop
inline function saveObject(obj)
{
    local f = FileSystem.getFolder(FileSystem.Desktop).getChildFile("myFile.json"); 
    f.writeObject(obj);
}

// Load the file 
inline function loadObject()
{
    local f = FileSystem.getFolder(FileSystem.Desktop).getChildFile("myFile.json"); 
    
    if (!f.isFile())
        return {}; // Invalid file, return empty object

    return f.loadAsObject(); // What you will have here is the same as the object you started with
}

[Chazrox]

@d-healey Thank you!

check my edit just in case.

[Chazrox]

@d-healey Im writing to a .json file and saving into UserPresets root folder. Is that all good?

[d.healey]

@Chazrox said in Read & Write JSON file || Basics:

UserPresets root folder. Is that all good?

You should only put user presets in there. If you want to save to a fixed location use the app data folder. https://docs.hise.dev/scripting/scripting-api/filesystem/index.html

[Chazrox]

@d-healey I was trying that one and I couldnt find where the file was going to.

Is AppData a folder within the plugin or is that a system folder?

[d.healey]

@Chazrox said in Read & Write JSON file || Basics:

Is AppData a folder within the plugin or is that a system folder?

It's a system folder - it's where the UserPresets folder lives, among other things.

• GNU/Linux: /home/username/.config/Company Name/Plugin Name/
• Windows: Users/username/AppData/Roaming/Company Name/Plugin Name/
• MacOS:~/Library/Application Support/Company Name/Plugin Name/

You can open it from the File menu in HISE btw.

[Chazrox]

@d-healey got it.

So I got that much working, the part im missing is....

How do I add new pairs to the object after its created?

[Chazrox]

wait dont give me the answer yet....im getting it. lol.

[Lindon]

@Chazrox said in Read & Write JSON file || Basics:

wait dont give me the answer yet....im getting it. lol.

hint - arrays are json "objects" too

[Chazrox]

@Lindon

via GIPHY

[Lindon]

@Chazrox

// create an array for objects
const var myObjectSet = [];
// Create an object
const myObj = {"name": "Dave", "age": 38, "country": "England"};
myObjectSet.push(myObj);

const myObj2 = {"name": "Lindon", "age": 150, "country": "England"};
myObjectSet.push(myObj2);

Console.print(trace(myObjectSet));

[Chazrox]

@Lindon nice! That was it! I get it now.

I just recently got comfortable sorting, cloning, flipping arrays so if this is anything like that im off to a good start.

Huge breakthrough for me here. haha.

Thank You @d-healey & @Lindon !

@Lindon said in Read & Write JSON file || Basics:

hint - arrays are json "objects" too

So are all array api's available for these too?

[Lindon]

@Chazrox said in Read & Write JSON file || Basics:

So are all array api's available for these too?

Arrays are just arrays - so yes the array API is applicable to them...but your array elements are "complex" objects so heaven knows how stuff like sort would work - if at all....

[Chazrox]

@Lindon Ok. I'll do some reading on that too.

@Lindon said in Read & Write JSON file || Basics:

heaven knows...

[d.healey]

@Lindon said in Read & Write JSON file || Basics:

but your array elements are "complex" objects so heaven knows how stuff like sort would work - if at all....

Custom sort function

[Chazrox]

@d-healey

can you take a look at this please?
// Im trying to add 'newPreset' to 'AttackTablePresets'

const var AttackTablePresets = 
{
		
	"name": "36...............vOLVxe+....9izwDzO...f+....9C...vO", 
	"name2": "36...............vOLVxe+....9izwDzO...f+....9C...vO", 
	"name3": "36...............vOLVxe+....9izwDzO...f+....9C...vO"
		
};

// SAVE PRESET BUTTON CONTROLS
inline function onSaveOkControl(component, value)
{	

	
	if (value)
	{
		local tableData0 = TableEnvelope1Pro.exportAsBase64(0);		
		local newPreset = {Newshit : tableData0};
		
		AttackTablePresets.insert(newPreset); 

// Im trying to add 'newPreset' to 'AttackTablePresets'
		
		Console.print("START TRACE" + trace(myObjectSet) + "END TRACE");
	}
};
Content.getComponent("SaveOk").setControlCallback(onSaveOkControl);

[d.healey]

@Chazrox

const myObj = {"name": "Dave", "age": 38, "country": "England"};

// To add something new you can use dot notation
myObj.newKey = newValue;

// Or you can use bracket notation - only really needed if you have spaces in the key or are using a variable to hold the key
myObj["newKey"] = newValue;

@Chazrox said in Read & Write JSON file || Basics:

AttackTablePresets.insert(newPreset);

This is for arrays, not objects. I think Lindon confused you :)

[Chazrox]

@d-healey oh wow..how do I find the rest of the dot.functions?

[d.healey]

@Chazrox It's not a function, it's accessing the property of the object.

Just like when you use .length to find out how many characters are in a string or elements in an array. If it doesn't have () at the end then it's not a function.

You're going to love my scripting course :)