JavaScript/Objects/Exercises

Topic: Objects

1. Be creative.

• Create an object which describes some of your physical or mental attributes.
• Show the object with the alert command.
• Show only the most important attribute of this object with the alert command.
• Add another property to the object. Show the complete object again.
• Delete the least important attribute. Show the complete object again.

Click to see solution

"use strict";// an example// literal notationconstme={height:"165 cm",weight:"63 kg",hairColor:"blond"};alert(JSON.stringify(me));alert(JSON.stringify(me.height));me.friendliness="medium";alert(JSON.stringify(me));deleteme.hairColor;alert(JSON.stringify(me));

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2. Articles of a warehouse.

• Create two objects shoe_1 and shoe_2 which characterize shoes. Use the literal notation.
• Create two other objects shirt_1 and shirt_2 which characterize shirts. First, create empty objects. Then, add attributes to the objects.
• Create an object warehouse and add all 4 objects to it.
• Show the price of the 4.-th product out of the warehouse object.

Click to see solution

"use strict";// literal notationconstshoe_1={category:"shoes",type:"sandals",size:8,color:"brown"};constshoe_2={category:"shoes",type:"high heels",size:7,color:"silver",price:"94.50"};// add propertiesconstshirt_1={};shirt_1.category="shirts";shirt_1.size="XL";shirt_1["color"]="blue";shirt_1["material"]="cotton";alert(JSON.stringify(shirt_1));// mixtureconstshirt_2={size:"S",color:"green"};shirt_2.category="shirts";shirt_2.price=19.99;alert(JSON.stringify(shirt_2));constwarehouse={prod_1:{...shoe_1},prod_2:{...shoe_2},prod_3:{...shirt_1},prod_4:{...shirt_2}};alert(JSON.stringify(warehouse));// the price of the 4.-th productalert(JSON.stringify(warehouse.prod_4.price));

This example is not very elegant but shows different techniques. In a production environment, you probably would use loops and arrays.