javascript tutorial - [Solved-5 Solutions] Get the last item in an array - javascript - java script - javascript array
Problem:
Here is my JavaScript code so far:
var linkElement = document.getElementById("BackButton");
var loc_array = document.location.href.split('/');
var newT = document.createTextNode(unescape(capWords(loc_array[loc_array.length-2])));
linkElement.appendChild(newT);
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Currently it takes the second to last item in the array from the URL. However we want to do a check for the last item in the array to be "index.html" and if so, grab the third to last item instead.
Solution 1:
if(loc_array[loc_array.length-1] == 'index.html'){
//do something
}else{
//something else.
}
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In the event that our server serves the same file for "index.html" and "inDEX.htML" we can also use: .toLowerCase().
Solution 2:
Not sure if there's a drawback, but this seems quite concise:
arr.slice(-1)[0]
or
arr.slice(-1).pop()
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Both will return undefined if the array is empty.
Solution 3:
- Use Array.pop:
var lastItem = anArray.pop();
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Solution 4:
A shorter version of what @chaiguy posted:
Array.prototype.last = function() {
return this[this.length-1];
}
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Solution 5:
Two options are:
var last = arr[arr.length - 1]
or
var last = arr.slice(-1)[0]
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The former is faster, but the latter looks nicer