Even when explicitly checking for null within an if statement, a Typescript Object may still be null

I'm attempting to retrieve a property from an object within an array using a specific index. Although I have checked for the object's existence, TypeScript is still warning that it might be null.

It's worth noting that in my project, "selectedIndex" is actually a state managed by React.

const arrayOfObjects: {bar:{baz: string; qux: string;}}[] = [{bar: {baz: 'value', qux: 'value'}}];

let selectedIndex: number = 0; // may vary

if (arrayOfObjects[selectedIndex].bar !== null) {
  doSomethingWith(arrayOfObjects[selectedIndex].bar.baz);
  // At this point, a typescript error may appear indicating that the "bar" Object could potentially be null
}

Any suggestions?

javascripttypescript

Answer №1

The issue arises from the selectedIndex being a dynamic react state value that may vary between executions.

let result = arrayOfObjects[selectedIndex].bar;   
if (result) { 
  performAction(result.baz) 
}

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