Encountering a service error that results in the inability to read properties of undefined when passing a method as a

Whenever I attempt to pass a service function as a parameter to another function, an error 'Cannot read properties of undefined myService' occurs during execution. However, calling this.myService.method() individually works perfectly fine without any issues. What could be causing this problem?

Here is the TypeScript file:

constructor(private myService: MyService)

 function1(): void {
        this.function2(this.myService.method)
    } 

function2(f: Function)
{
    f();

}

Answer №1

For more information, visit: Understanding the use of the "this" keyword in JavaScript

Approach 1 : Attaching the service context to "this" during initialization

function1(): void {
    this.function2(this.myService.method.bind(this));
    //or this.function2(() => this.myService.method());
} 

Approach 2 : Attaching the service context to "this" before calling a function

function2(f: Function)
{
    f.bind(this)();
}

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