VSCode : It is not showing java script functions in intellisense e.g. .toLowerCase

I'm on the VSCode team.

We cannot infer the types of JavaScript variables like categoryName in many cases, so we cannot know that toLowerCase is a valid method on categoryName. There are a few ways to fix this:

• Use jsdoc to specify the argument type:

  /** * @param {string} categoryName */ function foo(categoryName){ // `string` member completions avalible here } 

• Add a guard to the function:

  function foo(categoryName){ if (typeof categoryName !== 'string') return // `string` member completions available here } 

• Use TypeScript or Flow types

  function foo(categoryName: string){ // `string` member completions available here } 

Hope that helps.