Collectives™ on Stack Overflow

Find centralized, trusted content and collaborate around the technologies you use most.

Teams

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

I have been working on this for about 2 hours now, no to avail. I have searched the Internet, tried creating a condition, etc.

So I have a method in a VueJS component that looks like this:

paginate() {
  const test = this.$route.query.page;
  console.log(test);
  this.currPage = parseInt(test);
The word "test" on the last line has a red underline and I get an error message saying this:
const test: LocationQueryValue | LocationQueryValue[]
Argument of type 'LocationQueryValue | LocationQueryValue[]' is not assignable to parameter of type 'string'.
Type 'null' is not assignable to type 'string'.Vetur(2345)
How should I solve the TypeScript error without editing the TypeScript configuration file?
It means test can be null. Its type is likely string | null which is a union type. You need test it to eliminate the null case.
For example
paginate() {
  const test = this.$route.query.page;
  console.log(test);
  if (typeof test === 'string') {
    // `test` has type string here because of the predicate.
    this.currPage = parseInt(test);
Playground Link
Please note that the above solution, while indeed proper, changes the meaning of the original code, leaving this.currPage unchanged if test is not a string.
        
Thanks for contributing an answer to Stack Overflow!
Please be sure to answer the question. Provide details and share your research!
But avoid …
Asking for help, clarification, or responding to other answers.
Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.