javascript - Checking for multiple values in object -


this question has answer here:

what easiest way check undefined, null , "" in case:

i receiving object can have , of 3 states, , comes in form of:

images[0].url

images might not exists @ images might have url property of null images might have property of ""

i using if(images[0]), covers existence of [0], not deeper. how can solve this, without switch statement.

i tried this:

   if((object.images[0]) || (object.images[0].url)){  } else {  }

but if [0] exists , url not, this. uncaught typeerror: cannot read property 'url' of undefined

you error when object. images[0] not exist. avoid have gradual check this. 

 if(object.images && object.images[0] && object.images[0].url){  //do stuff }

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