Execute javascript command from variable

[rmurgia]

There is a sequence of ProdCode fields; in this case 1 - 3. I would like to populate the strCBFilter variable with the values contained in those fields using a loop:

document.frmXRefAttachMaint_01.ProdCode1 
document.frmXRefAttachMaint_01.ProdCode2 
document.frmXRefAttachMaint_01.ProdCode3 
 

The code creates each name by concatenating the number in the loop to the
prefix: document.frmXRefAttachMaint_01.ProdCode". Is there a way to have the program do this:

  strCBFilter = strCBFilter  +  document.frmXRefAttachMaint_01.ProdCode1 
 

using the value of variable strCBFilterCode which contains:
document.frmXRefAttachMaint_01.ProdCode1 with the number changing each time through the loop.

Full Code:

for(i = 1; i < 4; i++) 
{
  var strCBFilterCode = "document.frmXRefAttachMaint_01.ProdCode" + i + ".value";
 
   strCBFilter = strCBFilter  +  strCBFilterCode 
}
 

//The highlighted code populates the strCBFilter variable with the contents of the strCBFilterCode variable instead of the field the strCBFilterCode variable refers to. In other languages, I was able to execute commands after placing them in variables. Can this be done in Javascript?//

[Dormilich]

I guess you need to pass your strings through the eval() function to get it executed (otherwise it's just a bunch of strings).

[rmurgia]

It worked! Thank you.

[Dormilich]

I'm glad I could help.

[acoder]

Instead of eval(), you could use something like:

document.frmXRefAttachMaint_01.elements["ProdCode" + i].value

[rmurgia]

Thank you. Are there advantages of using this code:

document.frmXRefAttachMaint_01.elements["ProdCode" + i].value

over the eval() function?

[acoder]

The main benefit here is speed. Using bracket notation (member operators) is much faster - see Note on eval(). You shouldn't get into the habit of bunging everything into eval when there are better alternatives around. You'll notice the benefits when there's more code.

[rmurgia]

Okay, will give it a try and thanks again!