javascript - getElementById(array[x])? - Stack Overflow

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I'm trying to put an array in to getElementById for a loop purpose. It seems to be not working, how can I do this?

Edit: Sorry folks It says undefined.

    var lol=new Array( "test", "test2" );

var x = 0;
while( x == 4 ) {
    number = parseInt(document.getElementById(lol[x]).value);
    x++;
}

And i have inputs id named test and test2.

I'm trying to put an array in to getElementById for a loop purpose. It seems to be not working, how can I do this?

Edit: Sorry folks It says undefined.

    var lol=new Array( "test", "test2" );

var x = 0;
while( x == 4 ) {
    number = parseInt(document.getElementById(lol[x]).value);
    x++;
}

And i have inputs id named test and test2.

• javascript

Share Improve this question Follow edited Feb 1, 2010 at 17:51 Strawberry asked Feb 1, 2010 at 17:37 StrawberryStrawberry 68k5858 gold badges156156 silver badges206206 bronze badges 7

• 1 It seems to be not working : Any error messages,unexpected behavior, etc? Code would also help... – Felix Kling Commented Feb 1, 2010 at 17:40
• 9 <sillyRandomGuess reason="NoCodeProvided">You have a syntax error on line 31</sillyRandomGuess> – Josh Stodola Commented Feb 1, 2010 at 17:40
• Code snippet + error message = diagnosable problem. – David Berger Commented Feb 1, 2010 at 17:40
• @Josh your phraseology is hilariouser than mine. – David Berger Commented Feb 1, 2010 at 17:41
• getElementById() can't deal with the array. Just run through the array and do a single getElementById() on each member. – Pekka Commented Feb 1, 2010 at 17:46

 |  Show 2 more ments

3 Answers 3

Sorted by: Reset to default 8

Your while loop only works if x==4. Change this to:

while(x < lol.length)

To loop through all the elements in the array. Better yet, this will condense your loop:

var lol=new Array( "test", "test2" );
for( var x = 0; x < lol.length; x++ ) {
    number = parseInt(document.getElementById(lol[x]).value);
}

Try taking your array out of the quotes...

document.getElementById(lol[x]).value

The quotes turn it into a static string "lol[x]", when you want the value of the lol array at x index.

This replaces my earlier, less informed answer.

Hope this helps

You say you have number = parseInt(document.getElementById("lol[x]").value);

1. "lol[x]" is a string with that literal value, not the value that lol holds at index x. Use getElementById(lol[x])

2. parseInt may do unexpected things when you don't pass a radix. Use something like parseInt(document.getElementById(lol[x]).value, 10)

Finally, you aren't checking whether the element exists. Do something like:

var element = document.getElementById(lol[x]);
if (element) {
  number = parseInt(element.value, 10);
} else {
  // handle error or throw exception
}

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