Returning values out of for loop in javascript

Question

I have the following function:

 function getId(a){
 var aL = a.length;
 for(i = 0; i < aL; i++ ){
 return a[i][2].split(":", 1)[0];
 } 
 } 

and when using console.log() within the function instead of return I get all of the values in the loop, and the same goes for document.write. How can I access these values as a string for use in another section of my code?

Thank you in advance.

• Useless Code: The return statement immediately exits a function, returning the value of the expression that follows it. If you use a return statement in a loop without some sort of conditional like that it will preform the first pass and then exit. You need to collect them in a variable and return the variable after the loop. As others have suggested you'll probably want to store them in an array.
• jeffreynolte: Thanks Useless Code after looking into this a bit deeper I see where I was mistaken. Thank you

Answer 1

You can do that with yield in newer versions of js, but that's out of question. Here's what you can do:

function getId(a){
 var aL = a.length;
 var values = [];
 for(i = 0; i < aL; i++ ){
 values.push(a[i][2].split(":", 1)[0]);
 } 
 return values.join('');
} 

• fncomp: Shouldn't that be var values = [];?
• fabpico: yield link is dead. New is developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/…. Can't edit due to full edit queue.

Answer 2

You gotta cache the string and return later:

function getId(a){
 var aL = a.length;
 var output = '';
 for(var i = 0; i < aL; i++ ){
 output += a[i][2].split(":", 1)[0];
 } 
 return output;
} 

Answer 3

• The return statement breaks the loop once it is executed. Therefore consider putting the return statement outside the loop.
• Since you want to return a string, you will create a variable and assign it to an empty string.(This is where will append/add results from the loop.)
• return the string variable.

So final code will look like...

function getId(a){
 var result = '';
 var aL = a.length;
 for(i = 0; i < aL; i++ ){
 result += a[i][2].split(":", 1)[0];
 } 
 return result;
 }