I have actually a error around delete this.datastore. Ns tried to fix the problem. I gotten rid of the ‘’ however return not correct value. I desire to see variety of entries: 0 at last output. What is the problem ? thanks for help comments.

function clear()Object.keys(this.datastore).forEach(function(key, index) delete this.datastore;);Full Code:

// updates the finish Dictionary course definitionfunction Dictionary()this.add = add;this.datastore = new Array();this.find = find;this.remove = remove;this.showAll = showAll;this.count = count;this.clear = clear;function add(key, value)this.datastore = value;function find(key)return this.datastore;function remove(key)delete this.datastore;function showAll()var datastore = this.datastore;Object.keys(this.datastore).forEach( function(key, index) console.log(key + " -> " + datastore); );function count()var n = 0;Object.keys(this.datastore).forEach( function(key, index) ++n;);return n;function clear()Object.keys(this.datastore).forEach(function(key, index) delete this.datastore;);// making use of the count() and also clear() functionsvar pbook = new Dictionary();pbook.add("Raymond", "123");pbook.add("David", "345");pbook.add("Cynhia", "456");console.log("Number the entries: " + pbook.count());console.log("David"s extension: " + pbook.find("David") + " ");console.log("-------------------------");pbook.showAll();pbook.clear();console.log("Number that entries: " + pbook.count());


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hello snntaylan,

I think that in the clean function, you have to bind “this” to the originating context.

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So, making use of an arrow role or advertising datastore favor in the “showAll” role could deal with your problem.

function clear()Object.keys(this.datastore).forEach( (key, index) => delete this.datastore;);Or

function clear() permit datastore = this.datastore;Object.keys(this.datastore).forEach( function(key, index) delete datastore;);
can you please store to one topic in future, girlfriend don’t need to make a new one if it’s because that the same difficulty

*

Again, very same answer as the critical time, you room using an array as the data store, this can not work, it’s the dorn data structure. Arrays look prefer this:

<"a", "b", "c">You can’t collection the tricks to things that space not indices: variety cannot have actually a value “123” at index “Raymond”, that’s nonsensical