Tips for resolving the undefined error in TypeScript and React

Hey, I have this code snippet below which includes a call to the isSomeFunction method that returns true or false. However, there are times when the argument can be undefined. I only want to execute this function if selectedItems is not undefined. How can I achieve this?

<Button
  disabled={
    (selectedItems !== undefined && isSomefunction(assetIds, selectedItems)) || 
    isButtonDisabled 
  }/>

I'm getting an error saying "undefined is not assignable to type string." How do I check if selectedItems is not undefined before calling the isSomeFunction in this case to avoid the error?

If anyone could assist me with this, I would greatly appreciate it. Thank you!


Answer №1

If you want to verify the existence of selectedItems, you can do so with the following code snippet:

<Button
  disabled={(selectedItems && isSomefunction(assetIds, selectedItems) 
   || isButtonDisabled)}
/>

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