Ranting: checkboxes are not placed in array.

[Erwin Moller]

Grrr,

Forgive my ranting, but this really irritated me a lot.

<ranting>
I have a page with X checkboxes with the same name.

code like:
var numberofCB = document.forms.updateentitiesform["bla"].length;

ok?

What happens to my surprise:
numberofCB now only contains the number of checkboxes with that name IF
there are more than 1.
Otherwise it is undefined.

I need that for stuff like:
for (var i=0; numberofCB<i ;i++){
document.forms.updateentitiesform["bla[]"][i].checked = false;
}

Which fails when there is only 1 checkbox.

I don't know who decided to start creating the array ONLY when more than 1
element is found, but that guy forces me to start coding stupid branches.

Why not always make it an array?

</ranting>

Thanks for your time.

Regards,
Erwin Moller

[RobB]

Erwin Moller wrote:

Grrr,

Forgive my ranting, but this really irritated me a lot.

<ranting>
I have a page with X checkboxes with the same name.

code like:
var numberofCB = document.forms.updateentitiesform["bla"].length;

ok?

What happens to my surprise:
numberofCB now only contains the number of checkboxes with that name IF there are more than 1.
Otherwise it is undefined.

I need that for stuff like:
for (var i=0; numberofCB<i ;i++){
document.forms.updateentitiesform["bla[]"][i].checked = false;
}

Which fails when there is only 1 checkbox.

I don't know who decided to start creating the array ONLY when more than 1 element is found, but that guy forces me to start coding stupid branches.

Calm down a bit, and you'll see how silly that is.
refToForm.elementName and refToForm.elements.elementName only need one
variable slot to hold a reference to a single form control with a
unique name - why would an array be implemented? It's only needed for
multiple-same-named controls so, that's where you'll find it.
Why not always make it an array?

Because life is hard.

var el = document.forms.updateentitiesform.bla;
if (typeof el[0] != 'undefined')
{...got an array...

[Erwin Moller]

RobB wrote:

Erwin Moller wrote:

Grrr,

Forgive my ranting, but this really irritated me a lot.

<ranting>
I have a page with X checkboxes with the same name.

code like:
var numberofCB = document.forms.updateentitiesform["bla"].length;

ok?

What happens to my surprise:
numberofCB now only contains the number of checkboxes with that name IF

there are more than 1.
Otherwise it is undefined.

I need that for stuff like:
for (var i=0; numberofCB<i ;i++){
document.forms.updateentitiesform["bla[]"][i].checked = false;
}

Which fails when there is only 1 checkbox.

I don't know who decided to start creating the array ONLY when more

than 1

element is found, but that guy forces me to start coding stupid

branches.

Calm down a bit, and you'll see how silly that is.
refToForm.elementName and refToForm.elements.elementName only need one
variable slot to hold a reference to a single form control with a
unique name - why would an array be implemented? It's only needed for
multiple-same-named controls so, that's where you'll find it.

Sorry, but this gives me the penny-wise, poundfoolish feeling.
Because somebody wants to be smart and not use an array, the rest of the
world has to use branching in their javascript?

Does that make sense to you?

Really, this was a bad choice.

Why not always make it an array?
Because life is hard.

Maybe.
Another reason could be that the original creator was not thinking
everything through...

var el = document.forms.updateentitiesform.bla;
if (typeof el[0] != 'undefined')
{...got an array...

Yes, I know how to handle that.
That is unneeded code/branching in my humble opinion.

Really, I don't want to start ranting on you, but you make a stand for a bad
designdecision I think.

Thanks for your response anyway!
:-)
:-)
(Two smiley to make it up to you)

Regards,
Erwin Moller

[RobB]

Erwin Moller wrote:

RobB wrote:

Erwin Moller wrote:

Grrr,

Forgive my ranting, but this really irritated me a lot.

<ranting>
I have a page with X checkboxes with the same name.

code like:
var numberofCB = document.forms.updateentitiesform["bla"].length;

ok?

What happens to my surprise:
numberofCB now only contains the number of checkboxes with that

name IF

there are more than 1.
Otherwise it is undefined.

I need that for stuff like:
for (var i=0; numberofCB<i ;i++){
document.forms.updateentitiesform["bla[]"][i].checked = false;
}

Which fails when there is only 1 checkbox.

I don't know who decided to start creating the array ONLY when

more than 1

element is found, but that guy forces me to start coding stupid branches.

Calm down a bit, and you'll see how silly that is.
refToForm.elementName and refToForm.elements.elementName only need one variable slot to hold a reference to a single form control with a
unique name - why would an array be implemented? It's only needed for multiple-same-named controls so, that's where you'll find it.

Sorry, but this gives me the penny-wise, poundfoolish feeling.
Because somebody wants to be smart and not use an array, the rest of

the world has to use branching in their javascript?

Does that make sense to you?

Really, this was a bad choice.

Why not always make it an array?
Because life is hard.

Maybe.
Another reason could be that the original creator was not thinking
everything through...

var el = document.forms.updateentitiesform.bla;
if (typeof el[0] != 'undefined')
{...got an array...

Yes, I know how to handle that.
That is unneeded code/branching in my humble opinion.

Really, I don't want to start ranting on you, but you make a stand

for a bad designdecision I think.

Thanks for your response anyway!
:-)
:-)
(Two smiley to make it up to you)

Regards,
Erwin Moller

Here's the way I generally do it:

var f = document.forms.updateentitiesform,
ref = f.elements['bla[]'];
if (typeof ref[0] == 'undefined')
ref = [ref];
for (var i = 0, l = ref.length; i < l; i++)
ref[i].checked = false;

[Matt Kruse]

Erwin Moller wrote:

Sorry, but this gives me the penny-wise, poundfoolish feeling.
Because somebody wants to be smart and not use an array, the rest of
the world has to use branching in their javascript?

Rather, it's easier the way it is, IMO.

If an array was created every time for single form elements (since, you
know, _any_ type of form element can have multiple inputs with the same
name) then everyone's javascript code would look like

document.forms["formname"].elements["name"][0].value

Which is unnecessarill confusing for the 99% of the cases where there is
only a single input with the given name.

The best way to avoid branching every time you write your code is to use
generalized functions which give you the correct answer every time,
regardless of whether there are multiple inputs of the same name, if the
type of the input changes, etc.

At http://www.javascripttoolbox.com/validations/ I have getInputValue()
which will handle all these cases no matter what type of input it is, and
many people find that it makes life easier. Hope it helps.

--
Matt Kruse
http://www.JavascriptToolbox.com