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Bitovi

can.onKeyValue

  • Edit on GitHub

Defines how observable values can be listened to on a type.

@@can.onKeyValue( key, handler(newValue) )

The @@can.onKeyValue symbol points to a function that registers handler to be called back with the new value of key when key changes.

var obj = {
   handlers: {},
   setKeyValue: function(key, value){
       this[key] = value;
       var self = this;
       obj.handlers[key].forEach(function(handler){
           handler.call(self, value);
       });
   }
};

obj[canSymbol.for("can.onKeyValue")] = function(key, handler){
   if(!obj.handlers[key]) {
       obj.handlers[key] = [];
   }
   obj.handlers[key].push(handler);
}

Parameters

  1. key {String}:

    the string key to bind on changes to.

  2. handler {function(newValue)}:

    The handler must be called back with this as the instance of the observable.

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