Strategies for resolving the TypeScript error code TS7009?

I am currently new to Typescript programming and in the learning phase. I encountered a problem while coding and received an error in the backend console. Here is the code snippet that caused the error:

function employee(id:number,name:string) { 
   this.id = id 
   this.name = name 
} 

var emp = new employee(123,"Smith") 
employee.prototype.email = "<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="e2918f8b968aa2838081cc818d8f">[email protected]</a>" 

console.log("Employee 's Id:" +emp.id) 
console.log("Employee's name:"+emp.name) 
console.log("Employee's Email ID:"+emp.email)

The output on the browser console is as follows:

www.ts:10 Employee 's Id: 123
www.ts:11 Employee's name: Smith
www.ts:12 Employee's Email ID: <a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="dba8b6b2afb39bbab9b8f5b8b4b6">[email protected]</a>

The error in the Node console is:

[0] www/www.ts(6,15): error TS7009: 'new' expression, whose target lacks
a construct signature, implicitly has an 'any' type.

I would appreciate any help in resolving this issue. Thank you....

Answer №1

When working with TypeScript, it's important to remember that the new keyword should only be used with classes. To improve your code, consider restructuring it like this:

class Customer {
    id: number;
    name: string;
    email: string;

    constructor(id:number, name:string) {
        this.id = id;
        this.name = name;
    }
}

let cust = new Customer(456,"Johnson");
cust.email = "<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="39506874f1e9c8d6d5">[email protected]</a>";

The usage of the prototype property assignment in your initial code is unclear to me.

Answer №2

In case you prefer not to modify your current code, here is an alternative solution:

new (employee as any)(123, "smith")

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