Make a javascript function workable

Question

Here I have an array place.reviews but this array is sometimes empty so I need to write a function that first will check array is empty ot not and if not then to go getting data from array...

SO I try:

if (!!place.reviews) for(var i=0;i<place.reviews.length;i++){
  contentStr += '<br>'+ place.reviews[i].text+ '</br>';
}

But this code dont work for me?

Is here problem with if (!!place.reviews) or ... ?

You can try place.reviews[0] as condition to if statement. — Mr_Green
– Mr_Green, Commented Sep 16, 2013 at 11:18

Denys Séguret · Accepted Answer · 2013-09-16 11:18:42Z

2

That's because any not null object is "truthy".

Assuming your array might be undefined (if it can't there's no point in testing before the loop), you should do

if (place.reviews && place.reviews.length)

answered Sep 16, 2013 at 11:18

Denys Séguret

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1 Comment

Andy Over a year ago

This will continue if the array is empty tho.

Thomas Junk · Accepted Answer · 2013-09-16 11:20:29Z

2

Why check for emptyness at all?

for(var i=0;i<place.reviews.length;i++)

Your for loop-body doesn't execute at all if place.reviews.length is 0.

answered Sep 16, 2013 at 11:20

Thomas Junk

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1 Comment

Denys Séguret Over a year ago

+1 because if the array is guaranteed being defined and being an array, then it's the best solution.

Tomzan · Accepted Answer · 2013-09-16 11:18:15Z

1

Your if statement is not well formed, use this:

if (place.reviews.length) 
    for(var i=0;i<place.reviews.length;i++) {
        contentStr += '<br>'+ place.reviews[i].text+ '</br>';
    }

answered Sep 16, 2013 at 11:18

Tomzan

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Comments

Andy · Accepted Answer · 2013-09-16 11:18:39Z

1

if (place.reviews.length > 0)

answered Sep 16, 2013 at 11:18

Andy

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