Declare A Global Variable In Dart

Developing applications with Dart, the programming language developed by Google, requires understanding how to declare and use variables. This article will guide you through the process of declaring a global variable in Dart and explain its significance in detail.

Code snippet for declaring a global variable

// Defining a Global variable
var globalVar = "I am a Global Variable";

The above code snippet declares a global variable globalVar and assigns it with a string value I am a Global Variable.

Code Explanation for declaring a global variable

A variable in Dart is basically a named space in the memory which stores values. To execute any task in Dart, we are often needed to work with variables. Global variables, in particular, are variables that are defined outside of any function, class, or method and can be accessed from any part of the code.

Here’s how the declaration works:

1. var Keyword: In Dart, the var keyword is used to declare a variable. When you declare a variable with the var keyword, the Dart analyzer infers the variable’s type. In this case, since the variable globalVar is assigned with a string, it would infer the type as String.

2. globalVar: This is the name of the variable that we have declared. You can choose any name for a variable, but it’s always recommended to chose a name that represents the purpose or the values the variable is expected to hold.

3. "I am a Global Variable": This is the value that gets stored in the globalVar variable. In this case, a string value is being stored, but it could be any other data type depending on your requirements.

Remember that because globalVar is a global variable, it could be accessed and modified in any part of the code. It’s a good practice to declare a variable as global only when its required to be accessed from many different parts of the application. Otherwise, local variables should be preferred. It’s also important to know that unlike some programming languages, Dart does not have a specific keyword to declare a global variable. It’s the place of declaration that determines if it’s a global variable or not. If it’s outside any class, method or function, it’s a global variable.