Before developing the actual generic class, let's first understand the Generic class. TypeScript classes, called generics, can handle multiple types of data. It is the various parameters and is shown using angle brackets (). This represents the data type that the class will use to achieve this purpose. Type parameters can then be used in the class's properties and functions to make the class flexible and reusable with other data types.
We will do some briefings. Suppose in the example, the type parameter is represented as "T" and the attribute "value" of the simple generic class "MyGenericClass" is represented. Both "T" and "value" can be created. If this class is instantiated using an alternative type (such as "number" or "string"), the "value" property will have the appropriate type.
Since the same class can be used with multiple data types, this provides additional flexibility and reusability for your code. You can also use constraints to limit the kinds used as type parameters.
grammar
The syntax for creating a generic class in TypeScript is as follows -
class ClassName<TypeParameter> { // class properties and methods }
Where "ClassName" is the name of the class and "TypeParameter" is a placeholder for the data type that the class will use.
Example 1
This example demonstrates how to use generic classes in TypeScript to create a class that can handle multiple data types. The class is defined with a type parameter T, which is used in the properties and methods of the class, allowing the class to be flexible and reusable with different types of data. The "Queue" class has a private property called "data" which is an array of type T.
This class also has three methods: "enqueue", adds the item to the end of the queue; "dequeue", removes the item from the front of the queue; "peek", returns the item in the queue. to the front of the queue without deleting it. We create two instances of the Queue class, one for numbers and another for strings. This class can handle different data types, making our code more flexible and reusable.
class Queue<T> { private data: T[] = [] // add an item to the end of the queue enqueue(item: T) { this.data.push(item) } // remove an item from the front of the queue dequeue(): T | undefined { return this.data.shift() } // get the item at the front of the queue peek(): T | undefined { return this.data[0] } } let numberQueue = new Queue<number>() numberQueue.enqueue(1) numberQueue.enqueue(2) console.log(numberQueue.peek()) console.log(numberQueue.dequeue()) console.log(numberQueue.peek()) let stringQueue = new Queue<string>() stringQueue.enqueue('Hello') stringQueue.enqueue('world') console.log(stringQueue.peek()) console.log(stringQueue.dequeue()) console.log(stringQueue.peek())
When compiled, it will generate the following JavaScript code.
var Queue = /** @class */ (function () { function Queue() { this.data = []; } // add an item to the end of the queue Queue.prototype.enqueue = function (item) { this.data.push(item); }; // remove an item from the front of the queue Queue.prototype.dequeue = function () { return this.data.shift(); }; // get the item at the front of the queue Queue.prototype.peek = function () { return this.data[0]; }; return Queue; }()); var numberQueue = new Queue(); numberQueue.enqueue(1); numberQueue.enqueue(2); console.log(numberQueue.peek()); console.log(numberQueue.dequeue()); console.log(numberQueue.peek()); var stringQueue = new Queue(); stringQueue.enqueue('Hello'); stringQueue.enqueue('world'); console.log(stringQueue.peek()); console.log(stringQueue.dequeue()); console.log(stringQueue.peek());
Output
The above code will produce the following output -
1 1 2 Hello Hello world
Example 2
In this example, we will develop another generic class with two generic type properties. The "KeyValuePair" class has two private properties, "key" and "value", of type T and U respectively. This class also has two methods "getKey" and "getValue", which return key and value properties respectively.
This class can instantiate keys and values using data types such as numbers, strings, or objects. We create two instances of the KeyValuePair class, one with strings as keys and numbers as values, and another with strings as keys and objects as values. This class can use different data types as keys and values, making our code more flexible and reusable.
class KeyValuePair<T, U> { private key: T private value: U constructor(key: T, value: U) { this.key = key this.value = value } // method to get the key getKey(): T { return this.key } // method to get the value getValue(): U { return this.value } } let numberKeyValuePair = new KeyValuePair<string, number>('age', 20) console.log(numberKeyValuePair.getKey()) // "age" console.log(numberKeyValuePair.getValue()) // 20 let objectKeyValuePair = new KeyValuePair<string, object>('person', { name: 'Tutorialspoint', age: 10, }) console.log(objectKeyValuePair.getKey()) // "person" console.log(objectKeyValuePair.getValue()) // {name: "Tutorialspoint", age: 10}
When compiled, it will generate the following JavaScript code.
var KeyValuePair = /** @class */ (function () { function KeyValuePair(key, value) { this.key = key; this.value = value; } // method to get the key KeyValuePair.prototype.getKey = function () { return this.key; }; // method to get the value KeyValuePair.prototype.getValue = function () { return this.value; }; return KeyValuePair; }()); var numberKeyValuePair = new KeyValuePair('age', 20); console.log(numberKeyValuePair.getKey()); // "age" console.log(numberKeyValuePair.getValue()); // 20 var objectKeyValuePair = new KeyValuePair('person', { name: 'Tutorialspoint', age: 10 }); console.log(objectKeyValuePair.getKey()); // "person" console.log(objectKeyValuePair.getValue()); // {name: "Tutorialspoint", age: 10}
Output
The above code will produce the following output -
age 20 person { name: 'Tutorialspoint', age: 10 }
Using generic classes in TypeScript produces more flexible, reusable, and maintainable code. Additionally, TypeScript's type checking system ensures that types used in generic classes are used correctly at compile time, further improving the overall quality and safety of your code. Generic classes are a powerful feature of TypeScript that can be used to write more reliable and reusable code.
The above is the detailed content of How to develop generic classes. For more information, please follow other related articles on the PHP Chinese website!

JavaScript runs in browsers and Node.js environments and relies on the JavaScript engine to parse and execute code. 1) Generate abstract syntax tree (AST) in the parsing stage; 2) convert AST into bytecode or machine code in the compilation stage; 3) execute the compiled code in the execution stage.

The future trends of Python and JavaScript include: 1. Python will consolidate its position in the fields of scientific computing and AI, 2. JavaScript will promote the development of web technology, 3. Cross-platform development will become a hot topic, and 4. Performance optimization will be the focus. Both will continue to expand application scenarios in their respective fields and make more breakthroughs in performance.

Both Python and JavaScript's choices in development environments are important. 1) Python's development environment includes PyCharm, JupyterNotebook and Anaconda, which are suitable for data science and rapid prototyping. 2) The development environment of JavaScript includes Node.js, VSCode and Webpack, which are suitable for front-end and back-end development. Choosing the right tools according to project needs can improve development efficiency and project success rate.

Yes, the engine core of JavaScript is written in C. 1) The C language provides efficient performance and underlying control, which is suitable for the development of JavaScript engine. 2) Taking the V8 engine as an example, its core is written in C, combining the efficiency and object-oriented characteristics of C. 3) The working principle of the JavaScript engine includes parsing, compiling and execution, and the C language plays a key role in these processes.

JavaScript is at the heart of modern websites because it enhances the interactivity and dynamicity of web pages. 1) It allows to change content without refreshing the page, 2) manipulate web pages through DOMAPI, 3) support complex interactive effects such as animation and drag-and-drop, 4) optimize performance and best practices to improve user experience.

C and JavaScript achieve interoperability through WebAssembly. 1) C code is compiled into WebAssembly module and introduced into JavaScript environment to enhance computing power. 2) In game development, C handles physics engines and graphics rendering, and JavaScript is responsible for game logic and user interface.

JavaScript is widely used in websites, mobile applications, desktop applications and server-side programming. 1) In website development, JavaScript operates DOM together with HTML and CSS to achieve dynamic effects and supports frameworks such as jQuery and React. 2) Through ReactNative and Ionic, JavaScript is used to develop cross-platform mobile applications. 3) The Electron framework enables JavaScript to build desktop applications. 4) Node.js allows JavaScript to run on the server side and supports high concurrent requests.

Python is more suitable for data science and automation, while JavaScript is more suitable for front-end and full-stack development. 1. Python performs well in data science and machine learning, using libraries such as NumPy and Pandas for data processing and modeling. 2. Python is concise and efficient in automation and scripting. 3. JavaScript is indispensable in front-end development and is used to build dynamic web pages and single-page applications. 4. JavaScript plays a role in back-end development through Node.js and supports full-stack development.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 English version
Recommended: Win version, supports code prompts!

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

SublimeText3 Chinese version
Chinese version, very easy to use

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
