How to make a dictionary of dictionaries in JSON?

Question

Right now I have this structure in JSON

"Types":[  
            {  
               "LowCadence":[  
                  {  
                     "Reinforcement":"-1",
                     "Weight":"100",
                     "Message":"Pay attention. You're running low cadence. Your cadence is %d steps per minute."
                  }
               ]
            },
            {  
               "NormalCadence":[  
                  {  
                     "Reinforcement":"0",
                     "Weight":"100",
                     "Message":"Great, your cadence is on target. Cadence is %d steps per minute.",
                     "EnforcementSound":"ding"
                  }
               ]
            },
            {  
               "HighCadence":[  
                  {  
                     "Reinforcement":"1",
                     "Weight":"100",
                     "Message":"Slow down. You're running over your planned cadence. Cadence is %d steps per minute."
                  }
               ]
            }
         ]

But I would like it to have this structure

Does anyone know how to write it in JSON?

Answer 1

I believe your JSON would look something like:

var Types = {
    NormalHR: {
        Reinforcement: 0,
        Weight: 100,
        Message: 'Great! Your heart rate is in the zone.',
        EnforcementSound: 'ding'
    },
    HighHR: {
        Reinforcement: 1,
        Weight: 100,
        Message: 'Slow down. Your heart rate is too high!'
    },
    LowHR: {
        Reinforcement: -1,
        Weight: 100,
        Message: 'Speed up. Low heart rate.'
    }
};

As @Balder says in their answer, you can then access use dictionary-style syntax, like:

• Types['NormalHR']['Reinforcement']

You could also use property-accessor syntax, like:

• Types.NormalHR.Reinforcement

The reason I didn't include the "type" of each item, is that you can easily infer it for building your grid - as follows:

• typeof Types.NormalHR.Reinforcement (this will return "number")
• typeof Types.NormalHR.Message (this will return "string")

Similarly, to get the counts - you can count the properties of a specific object. In modern browsers, try:

• Object.keys(Types.NormalHR).length (this will return 2)

For older browsers, refer to other methods here: How to efficiently count the number of keys/properties of an object in JavaScript?

Hope this helps!