Accessing array elements from the array name received as a String in Javascript?

Question

I have a function that receives an array of Strings. These are the names of variables I'm supposed to concat together.

Something like:

function createArray(varNames){
 varNames.each( function(varName){
 someArray = someArray.concat(varName.items);
 });
}
createArray(["array1", "array2"]);

I don't know how to take a string and select the variable named after it. Any way of doing this in Javascript?

Answer 1

Depends of the scope where the variable was defined. If it was defined in the global scope (inside a browser) you could access it via the window object.

For example:

var arr1 = [1,2,3,4,5];
window['arr1']; // 1,2,3,4,5

Answer 2

try window[varName] - drop the .items

for example

function createArray(varNames,theScope){
 theScope = theScope || window;
 varNames.each( function(varName){
 someArray = someArray.concat(theScope[varName]);
 });
}

createArray(["array1", "array2"]);

if you have

var array1=[...];
var array2=[...];

or

createArray(["array1", "array2"],myScope);

if you have

var myScope = {
 "array1":[...],
 "array2":[...],
}

Answer 3

You can pass variables in an array rather than passing a string.