Basic «reflection» in JS [duplicate]

This question already has an answer here:

• Get array of object's keys 4 answers

Can I:

1. Get JS object properties as array?
2. Get property by name (like obj.prop('propname').val())
3. Set property value by name (obj.prop('propname').val('WAT?'))

Why I need this: I have some model declaration and want parse JSON data according to this.