how to put a declaration in a if-function?

Question

hey community, I am making a pdf with information from a website. My problem is the image. If there is an image it works with the codes: const first_picture_url: string = product.pictures[0].url; const other_picture_urls: string[] = product.pictures.filter( (_: { url }, index: number) => index > 0).map((picture: { url }) => picture.url); If there is no image, i get the Error TypeError: Cannot read property 'url' of undefined. i found out i could prevent this with if (product.pictures.length but if i try to put the first codes in this if-function it doesnt work. My try: if (product.pictures.length>0){ const first_picture_url: string = product.pictures[0].url; const other_picture_urls: string[] = product.pictures.filter( (_: { url }, index: number) => index > 0).map((picture: { url }) => picture.url); } else { const first_picture_url: string = String(product.airCoolingIntegrated); } it doesnt work, i get the message "first_picture_url" is declared but its value is never read" i just want these lines not be initiated if the length of the attribute is 0. (so no picture existing). Can anyone help me with that maybe? Greetings

Sachin Singh · Answer

declare the variable outside of the if statement const first_picture_url: string=null; roduct.pictures.length !=null){ first_picture_url: string = product.pictures[0].url; other_picture_urls: string[] = product.pictures.filter( (_: { url }, index: number) => index > 0).map((picture: { url }) => picture.url); else first_picture_url: string = String(product.airCoolingIntegrated);

Sachin Singh · Answer

do this instead if (product.pictures!=null) { // your code here }

BD One · Answer

@Sachin If i use your Code, IT has The Same Error. "First_picture_url ist declared but its value is never read" typescript is telling me If i declare it, i should also use it...