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Bozhong Tao
18,365 PointsConcatenation error in video?
notice from 2:11 - 2:19 in this video: https://teamtreehouse.com/library/ajax-basics/ajax-and-apis/displaying-the-photos
the concatenation in the $.each function, it is written like this:
$.each(array, function(index, item) {
alert('item ' + index + ' is ' item);
});
however, in the for loop example after this(2:21 - 2:30), it is written like this:
for (var i = 0; i < array.length; i ++) {
alert('item ' + index + ' is ' + item);
};
notice the concatenation difference in each example, the one using jQuery function didn't have '+' between ' is ' and item variable. Is this a typo or this will produce the same result? Thanks for the advise.
2 Answers
andren
28,558 PointsMissing the + between ' is ' and item inside the $.each method is indeed a typo.
When concatenating values you always need to use the + operator to merge two things together, using a space as shown in your code example will not work. If the code shown in the video had actually been executed you would have received a SyntaxError.
Adam Beer
11,314 PointsActually they do the same thing, just a little different. The for loop is the popular.
or
Check this course JavaScript Loops, Arrays and Objects
Bozhong Tao
18,365 PointsHi Adam Beer , thanks for the feedback. However, I am aware that the two does the same job :)
What am trying to point out is the potential concatenate error in the video. (If it is indeed a typo)
Bozhong Tao
18,365 PointsBozhong Tao
18,365 PointsThanks andren ! Yes it took me some time to figure out this is indeed a typo. Thought it was some syntax I missed out in the first place. CC Dave McFarland