add js foreach elements

content/posts/2022/javascript/foreach.md

@@ -0,0 +1,60 @@
+---
+title: "Перебор элементов в JavaScript"
+date: 2022-11-02T23:52:56+03:00
+draft: false
+tags: [javascript, development, tutorial]
+---
+
+## Массивы
+
+Синтаксис:
+
+```javascript
+arr.forEach(function callback(currentValue, index, array) {
+    //your iterator
+}[, thisArg]);
+```
+
+Пример:
+
+```javascript
+let exampleArray = [
+    {name: 'Alex', age: 15},
+    {name: 'Regina', age: 21},
+];
+
+exampleArray.forEach((value, index) => {
+    console.log(`${index} - ${value.name}: ${value.age}`);
+});
+```
+
+[Documentation on Developer.Mozilla](https://developer.mozilla.org/ru/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach)
+
+## Объекты
+
+Синтаксис:
+
+```javascript
+Object.entries(obj).forEach(([key, value]) => {
+    console.log(`${key} ${value}`); // "a 5", "b 7", "c 9"
+});
+```
+
+Пример:
+
+```javascript
+let Buttons = {
+    up: {x: 0, y: 10, pressed: false, callback: 'fButtonUp'},
+    down: {x: 0, y: 0, pressed: false, callback: 'fButtonDown'},
+    start: {x: 150, y: 50, pressed: false, callback: 'fButtonStart'},
+};
+
+Object.entries(Buttons).forEach(([key, value]) => {
+    console.log(key, value.pressed);
+    console.log(`Pos: ${Buttons[key].x}x${Buttons[key].y}`);
+    console.log();
+    console.log();
+});
+```
+
+[Documentation on Developer.Mozilla](https://developer.mozilla.org/ru/docs/Web/JavaScript/Reference/Global_Objects/Object/entries)