Get Programming with JavaScript

Get Programming with JavaScript - Listing 8.10

Listing 8.10 - Using the arguments passed by forEach - compact

[ "Dax", "Jahver", "Kandra" ].forEach(function (item, index, wholeArray) {
    console.log("Item: " + item);
    console.log("Index: " + index);
    console.log("Array: " + wholeArray);
});

Further Adventures

Listing 8.10 - Using the arguments passed by forEach - compact - Task 1

Create an array of rectangle objects. Each rectangle should have a length property and a width property.

var rectangles = [
    {
        length: 10,
        width: 6
    },
    {
        length: 8,
        width: 7
    },
    {
        length: 2.5,
        width: 2.5
    }
];

Listing 8.10 - Using the arguments passed by forEach - compact - Task 2

Define an assignArea function that takes a rectangle as an argument and assigns an area property holding the area of the rectangle.

var rectangles = [
    { length: 10,  width: 6   },
    { length: 8,   width: 7   },
    { length: 2.5, width: 2.5 }
];

var assignArea = function (rect) {
    rect.area = rect.length * rect.width;
};

Listing 8.10 - Using the arguments passed by forEach - compact - Task 3

Define a showInfo function that takes a rectangle as an argument and displays its properties on the console.

var rectangles = [
    { length: 10,  width: 6   },
    { length: 8,   width: 7   },
    { length: 2.5, width: 2.5 }
];

var assignArea = function (rect) {
    rect.area = rect.length * rect.width;
};

var showInfo = function (rect) {
    var info = "The rectangle with length " + rect.length;
    info += " and width " + rect.width;
    info += " has area " + rect.area;
    console.log(info);
};

Listing 8.10 - Using the arguments passed by forEach - compact - Task 4

Use forEach and your two functions to display info about each of the rectangles in the array.

var rectangles = [
    { length: 10,  width: 6   },
    { length: 8,   width: 7   },
    { length: 2.5, width: 2.5 }
];

var assignArea = function (rect) {
    rect.area = rect.length * rect.width;
};

var showInfo = function (rect) {
    var info = "The rectangle with length " + rect.length;
    info += " and width " + rect.width;
    info += " has area " + rect.area;
    console.log(info);
};

rectangles.forEach(function (rect) {
    assignArea(rect);
    showInfo(rect);
});