Do neither of those things. Make a javascript “class”: var MyClass = function () { var privateVar; //private var privateFn = function(){}; //private this.someProperty = 5; //public this.anotherProperty = false; //public this.someFunction = function () { //public //do something }; }; MyNamespace.MyClass = new MyClass(); One with static vars: var MyClass = (function(){ var static_var; … Read more
This is easily done with the Array.prototype.map() function: var keyArray = objArray.map(function(item) { return item[“key”]; }); If you are going to do this often, you could write a function that abstracts away the map: function pluck(array, key) { return array.map(function(item) { return item[key]; }); } In fact, the Underscore library has a built-in function called … Read more
You could use Object.assign in combination with the ternary operator: let data = Object.assign({}, first === null ? null : {first}, … ); This works because Object.assign will skip over null parameters. If you are sure that the property value is not going to be “falsy”, then it would be bit shorter to write: let … Read more
For more generic advice on debugging this kind of problem MDN have a good article TypeError: “x” is not a function: It was attempted to call a value like a function, but the value is not actually a function. Some code expects you to provide a function, but that didn’t happen. Maybe there is a … Read more
In ECMAScript, starting from ES5, reserved words may be used as object property names “in the buff”. This means that they don’t need to be “clothed” in quotes when defining object literals, and they can be dereferenced (for accessing, assigning, and deleting) on objects without having to use square bracket indexing notation. That said, reserved … Read more
For what it’s worth, since underscore.js you can now use _.object() var some_map = _.object(_.map(some_object_array, function(item) { return [item.id, item] }));
Here’s a non-jQuery version: function toQueryString(obj) { var parts = []; for (var i in obj) { if (obj.hasOwnProperty(i)) { parts.push(encodeURIComponent(i) + “=” + encodeURIComponent(obj[i])); } } return parts.join(“&”); }
well, this using lodash or vanilla javascript it depends on the situation. but for just return the array that contains the differences can be achieved by the following, offcourse it was taken from @1983 var result = result1.filter(function (o1) { return !result2.some(function (o2) { return o1.id === o2.id; // return the ones with equal id … Read more
The “braces” are making an object literal, i.e. they create an object. It is one argument. Example: function someFunc(arg) { alert(arg.foo); alert(arg.bar); } someFunc({foo: “This”, bar: “works!”}); the object can be created beforehand as well: var someObject = { foo: “This”, bar: “works!” }; someFunc(someObject); I recommend to read the MDN JavaScript Guide – Working … Read more
Nobody seems to be explaining the difference between an array and an object. [] is declaring an array. {} is declaring an object. An array has all the features of an object with additional features (you can think of an array like a sub-class of an object) where additional methods and capabilities are added in … Read more