Dart Cheat Sheet for TypeScript Developers

Welcome to the "Dart Cheat Sheet for TypeScript Developers". This article is meant to be a quick reference guide for software developers already familiar with TypeScript who are looking to expand their expertise into Dart.

Variables and Constants

// TypeScript
var myVar: string = "hello world";
let myLet: string = "hello world";
const myConst:string = "hello world";

// Dart
var myVar = "hello world"; // Inferred type
const String myConst = "hello world"; // Compile-time constant
final String myFinal = "hello world"; // Set the value at run-time once
late String myLateVar; // Set the value later

async/await

// TypeScript
async myFunction (myArg: string): Promise<void> {
  // await something
}

// Dart
Future<void> myFunction (String myArg) async {
  // await something
}

Console.log / Print

// TypeScript
console.log("hello world");

// Dart
print("hello world");

String interpolation

// TypeScript
const welcomeText = `Hello ${firstName}`;

// Dart
final welcomeText = 'Hello $firstName';

setTimeout

// TypeScript
const myTimeout = setTimeout(() => {
  // do something
}, 1000);
clearTimeout(myTimeout);

// Dart
import 'dart:async';
...
final myTimeout = Timer(Duration(seconds: 1), () {
  // do something
});
myTimeout.cancel();

setInterval

// TypeScript
const myInterval = setInterval(() => {
  // do something
}, 1000);
clearInterval(myInterval);

// Dart
import 'dart:async';
...
final myInterval = Timer.periodic(Duration(seconds: 1), (timer) {
  // do something
});
myInterval.cancel();

Comments

Post a Comment

Popular posts from this blog

Parameters Sent by TinyWebDB in App Inventor for Android

TinyWebDB is a component in App Inventor for Android that lets your app communicate with a web page in order to set or retrieve values, rather than storing them on the phone itself. I wanted to know what the TinyWebDB component sends to the web page when it tries to set or retrieve values, so I used Kodingen this morning to write a PHP script that takes the form fields and values sent to the page and writes them to a file. Here is what I found: TinyWebDB.StoreValue sends these parameters: tag value TinyWebDB. GetValue sends this parameter: tag So if you write your own PHP page for TinyWebDB to connect to, you can know if TinyWebDB is trying to store a value if the "value" key exists in the $_POST array. If the "value" key doesn't exist in the $_POST array then you know that TinyWebDB is only trying to retrieve the value for the given tag. As an alternative to using the method outlined by Google , you could use TinyWebDB with your own script written in an...
Read more

Adobe® Flex® Combobox: Selecting an Item Without Using SelectedIndex

In Adobe Flex, in order to select an item in a ComboBox, you use the .selectedIndex property. However, there might be times that you want to specify the item to be selected based on something other than it's position in the list. I have found two potential solutions: ComboBox2 from Ben Forta, Flex evangelist, is a ComboBox component which allows you to specify a "selectedValue" property.   VAComboBox  from Codieron, LTD. (BSD license) Copyright Notice: Adobe, and Flex are either registered trademarks or trademarks of Adobe Systems Incorporated in the United States and/or other countries.
Read more