Save a callback function as a variable and execute it independently from the higher-order function

I am trying to assign a callback function to a component variable... For example:

...
export class MyComponent {
       private myCompVar: any;

       myFunc = function(callback: (number) => void): void {
              this.myCompVar = callback;
       }
}

...and then later call this callback function from within another function in MyComponent. For instance:

...
export class MyComponent {
       private myCompVar: any;
       ...
       myOtherFunc(event): void {
               ...
               this.myCompVar(callbackParam);
       }
}

However, I am facing an issue where 'this.myCompVar' is undefined when attempting to call it inside 'myOtherFunc'. Despite setting the callback correctly in 'myFunc' and confirming its type as 'function', I encounter this error. 'myOtherFunc' is being called after 'myFunc', as expected.

Any assistance on this matter would be highly appreciated!

Answer №1

When the function keyword is utilized, there may be a loss of the correct context for this. A better alternative would be to use a lambda (fat arrow function) which binds correctly to the intended this context:

updateFunction = (callback: (number) => void): void => {
    this.myVariable = callback;
}

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