In Angular 11, there is a potential for an object to be null

When running the code below, I encountered an error stating Object is possibly null in line +localStorage.getItem('PID'):

newPropID() {
  if (localStorage.getItem('PID')) {
    localStorage.setItem('PID', String(+localStorage.getItem('PID') + 1));
    return +localStorage.getItem('PID');
  } else {
    localStorage.setItem('PID', '101');
    return 101;
  }
}

I am looking for a solution to check if there is already a record stored in local storage and add a new one. How can I rectify this issue?

typescriptlocal-storageangular11

Answer №1

When you use Typescript, it has the ability to deduce potential values if you encapsulate them into a variable:

generateNewID() {
  const ID = localStorage.getItem('ID');
  if (ID) {
    const updatedID = String(+ID + 1);

    localStorage.setItem('ID', updatedID);
    return updatedID;
  } else {
    localStorage.setItem('ID', '101');
    return 101;
  }
}

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