Implement custom forEach methods for array manipulation

Author: Wcoder547

arrayqs_1/index.js

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+//Qs : There is an array which contains extra elements. You have to find the core element of array.
+
+//Ans:
+
+Array.prototype.newName = "waseem akram";
+
+const newArr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+// for (let v in newArr) {
+//   console.log(v);
+// } //0
+// 1
+// 2
+// 3
+// 4
+// 5
+// 6
+// 7
+// 8
+// 9
+// newName
+
+for (let v in newArr) {
+  if (newArr.hasOwnProperty(v)) {
+    console.log(v);
+  }
+}
+//1,2,3,4,5,6,7,8,9,10

customForeach(1)

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+//Qs:implement custom forEach method
+//Ans:
+Array.prototype.customForEachOne = function (callback) {
+  for (let i = 0; i < this.length; i++) {
+    callback(this[i], i, this);
+  }
+};
+
+const numbers = [10, 20, 30];
+
+numbers.customForEachOne(function (element, index, array) {
+  console.log(`Element at index ${index}: ${element} In array: ${array}`);
+});
+// Output:
+// Element at index 0: 10 In array: 10,20,30
+// Element at index 1: 20 In array: 10,20,30
+// Element at index 2: 30 In array: 10,20,30\
+
+Array.prototype.customForEachTwo = function (callback, thiscontext) {
+  if (typeof callback !== "function") {
+    throw new TypeError("callback is not a function");
+  }
+  for (let i = 0; i < this.length; i++) {
+    callback.call(thiscontext, this[i], i, this);
+  }
+};
+
+const user = {
+  name: "Ali",
+  logColor: function (color, index) {
+    console.log(`${this.name} likes color #${index + 1}: ${color}`);
+  },
+};
+
+const colors = ["purple", "orange", "cyan"];
+
+colors.customForEachTwo(user.logColor, user); // Passing `user` as thiscontext
+// explaination:- .call() used for custom this context calling.
+// Output:
+// Ali likes color #1: purple
+// Ali likes color #2: orange
+// Ali likes color #3: cyan