Connecting data with Angular

Recently, as part of my learning journey with Angular, I encountered an intriguing issue. While working on my code, I noticed that the error popped up in my code editor (VSCode) but not when running the code in the browser.

The dilemma stemmed from setting a property to be interpreted as a string initially, only to update it to a number within the constructor. Here's a snippet of the code:

export class SandboxComponent{
    name:string = 'John Doe';

    constructor(){
        this.name = 34;
    }
}

You can view screenshots comparing how the code behaves differently in the browser versus VSCode: Browser View, VSCode View.

While VSCode correctly flags an error about assigning a number to a string, the browser seems to convert it without any issues. This discrepancy raises the question - why does the error show in VSCode but not affect the browser output?

Answer №1

Despite the presence of an error in your TypeScript code (redefining a variable with a value of a different type), the transpiler successfully generates JavaScript code.

The browser then executes the JavaScript code. In contrast to TypeScript, JavaScript is dynamically typed, enabling the redefinition of variables with values of different types without triggering an error in the browser.

Answer №2

After declaring the name variable as a string, attempting to assign a number to it directly violates TypeScript rules. To resolve this issue, consider using the following approach:

this.name = new String(34).toString();

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