How do I shift an array of items up by 4 places in Javascript

javascript arrays shift
Darryl Hebbes picture Darryl Hebbes · Oct 5, 2009 · Viewed 12.2k times · Source

How do I shift an array of items up by 4 places in Javascript?

I have the following string array:

var array1 = ["t0","t1","t2","t3","t4","t5"];

I need a function convert "array1" to result in:

// Note how "t0" moves to the fourth position for example
var array2 = ["t3","t4","t5","t0","t1","t2"];

Thanks in advance.

Answer

Russ Cam picture Russ Cam · Oct 5, 2009 
array1 = array1.concat(array1.splice(0,3));

run the following in Firebug to verify

var array1 = ["t0","t1","t2","t3","t4","t5"];
console.log(array1);
array1 = array1.concat(array1.splice(0,3));
console.log(array1);

results in 

["t0", "t1", "t2", "t3", "t4", "t5"]
["t3", "t4", "t5", "t0", "t1", "t2"]

Related questions

Change elements positions in an array and shift elements in between

I would like to pick an element in an array, move it to another index, and then "shift/rotate" the "in-between" elements by 1. Imagine a drag and drop functionality, if the index from is less than index to, then I …

Read More
How can I remove a specific item from an array?

I have an array of numbers and I'm using the .push() method to add elements to it. Is there a simple way to remove a specific element from an array? I'm looking for the equivalent of something like: array.remove(…

Read More
For-each over an array in JavaScript

How can I loop through all the entries in an array using JavaScript? I thought it was something like this: forEach(instance in theArray) Where theArray is my array, but this seems to be incorrect.

Read More