return false alternative

[Peter Afonin]

Hello,

I'm using Javascript in ASP.NET application to check whether at least one
checkbox in datagrid has been checked. If validation fails, the user gets a
warning. If he clicks OK, the form is submitted, if Cancel - nothing should
happen.

The ASP.NET code looks like this:

btnSubmit.Attributes.Add("onClick", "if (!(" & sClientSideValidate.ToString
& "))" _
& "{ confirm('You have not selected any DRs. Are you sure you want to submit
change?');return false}")

All validation is in sClientSideValidate.

The problem is with "return false". ASP.NET doesn't like the word "return".
If I use it - all my ASP.NET validation controls don't work. For instance,
if I use "return confirm" - I have a problem, if I use just "confirm" - I
have no problem.

Same with "return false". But in this case I don't know what could I use
instead of "return false". I have to use something to cancel form submission
if the user clicks "Cancel".

I'm not an expert in Javascript, so I hope someone could tell me - what
could I use instead of "return false" to get the same results?

I would appreciate your help.

Thank you,

 

[Tom Cole]

Hello,

I'm using Javascript in ASP.NET application to check whether at least one
checkbox in datagrid has been checked. If validation fails, the user gets a
warning. If he clicks OK, the form is submitted, if Cancel - nothing should
happen.

The ASP.NET code looks like this:

btnSubmit.Attributes.Add("onClick", "if (!(" & sClientSideValidate.ToString
& "))" _
& "{ confirm('You have not selected any DRs. Are you sure you want to submit
change?');return false}")

All validation is in sClientSideValidate.

The problem is with "return false". ASP.NET doesn't like the word "return".
If I use it - all my ASP.NET validation controls don't work. For instance,
if I use "return confirm" - I have a problem, if I use just "confirm" - I
have no problem.

Same with "return false". But in this case I don't know what could I use
instead of "return false". I have to use something to cancel form submission
if the user clicks "Cancel".

I'm not an expert in Javascript, so I hope someone could tell me - what
could I use instead of "return false" to get the same results?

I would appreciate your help.

Thank you,

First of all your closing brace is not in the proper place, it should
be before the return statement. But you can do even better than that.
The confirm box returns the users selection so you can check for true
or false and return it:

I have no experience with ASP (I'm a JSP developer) but it should look
something like this:

btnSubmit.Attributes.Add("onclick", "function() = { if (! " &
sClientSideValidate.ToString & ") { return confirm('You have not
selected any DRs. Are you sure you want to submit change?'); } }");

HTH.

 

[Peter]

Thank you very much.

The function you wrote looks perfectly correct to me. However, I'm
getting error "Expected: '{'", and I cannot figure out where it could
be expected.

This is how this function looks in the source:

<input type="submit" name="btnSubmit" value="Submit"
onclick="function() = { if (! dgReport__ctl2_chkConf.checked ||
dgReport__ctl3_chkConf.checked ||dgReport__ctl4_chkConf.checked ||
dgReport__ctl5_chkConf.checked ||dgReport__ctl6_chkConf.checked)
{ return confirm('You have not selected any DRs. Are you sure you want
to submit change?'); } }if (typeof(Page_ClientValidate) == 'function')
Page_ClientValidate(); " language="javascript" id="btnSubmit"
class="button" />

Thank you,

Peter

 

[Peter]

And one more thing I'd like to mention. I'm afraid this code will also
never work for me due to the same statement "return". This statement
breaks all further code execution, that's why my other validation
controls don't work. Is there a way to avoid it?

Thanks again,

Peter

 

[Richard Cornford]

And one more thing I'd like to mention. I'm afraid this code
will also never work for me due to the same statement "return".
This statement breaks all further code execution, that's why my
other validation controls don't work. Is there a way to avoid
it?

<snip>

It is hard to believe that ASP.NET could really be as bad as you
have just described. However, as you are constructing your
javascript code from string values in another leagues couldn't
you disguise the "return" keyword? In javascript we could do:-

"ret"+"urn false;"

- or:-

"\u0072eturn false;" //replacing the r with its unicode escape sequnce.

- for example, thought there would be no need in javascript.

Richard.

 

[Peter]

There is nothing bad about ASP.NET. "return" stops any further
Javascript code execution, added to the button "onclick" event. That's
why any further client side validation is not possible. It's all
understandable. So playing with the characters won't help here.

Thanks,

Peter

 

[Richard Cornford]

There is nothing bad about ASP.NET.

<snip>

Then why did you write "ASP.NET doesn't like the word "return"."? And why are you showing us server code
if your problem is only with the client-side code?

Richard.

 

[Peter Afonin]

I guess the word "doesn't like" wasn't the right one.

In this particular case the javascript can be added only using the
server-side code, because I have to itirate through the hundreds of rows of
the datagrid. Well, maybe it's possible to use pure javascript without
server-side code, but I don't know how. That's why I was showing how I added
this code - using the server-side scripts. But the output in the HTML source
is this (example):

<input type="submit" name="btnSubmit" value="Submit"
onclick="function() = { if (! dgReport__ctl2_chkConf.checked ||
dgReport__ctl3_chkConf.checked ||dgReport__ctl4_chkConf.checked ||
dgReport__ctl5_chkConf.checked ||dgReport__ctl6_chkConf.checked)
{ return confirm('You have not selected any DRs. Are you sure you want
to submit change?'); } }if (typeof(Page_ClientValidate) == 'function')
Page_ClientValidate(); " language="javascript" id="btnSubmit"
class="button" />

Peter

 

[Richard Cornford]

I guess the word "doesn't like" wasn't the right one.

Attributing the attitude to ASP.NET doesn't appear to be right either.

In this particular case the javascript can be added only using
the server-side code, because I have to itirate through the
hundreds of rows of the datagrid. Well, maybe it's possible
to use pure javascript without server-side code, but I don't
know how.

That would be irrelevant.

That's why I was showing how I added this code - using the server-side scripts.

Yes, not knowing what you are doing will have you looking form the wrong thing in the wrong place much
of time.

But the output in the HTML source is this (example):

<input type="submit" name="btnSubmit" value="Submit"
onclick="function() = { if (! dgReport__ctl2_chkConf.checked ||

^^^^^^^^^^^^^^
There are at least two syntax errors there, so this will never even get to the point of executing a
return statement.

dgReport__ctl3_chkConf.checked ||dgReport__ctl4_chkConf.checked ||

^^^^^^^^^^^^^^^^^^^^^^^
You are not attempting anything cross-browser then?

dgReport__ctl5_chkConf.checked ||dgReport__ctl6_chkConf.checked)
{ return confirm('You have not selected any DRs. Are you sure you want
to submit change?'); } }if (typeof(Page_ClientValidate) == 'function')
Page_ClientValidate(); " language="javascript" id="btnSubmit"

^^^^^^^^^^^^^^^^^^^^
What on earth is that bizarre attribute doing there?

class="button" />

<snip>

The logic you seem to want to implement is more like:-

if(
(
!(
(dgReport__ctl2_chkConf.checked)||
(dgReport__ctl3_chkConf.checked)||
(dgReport__ctl4_chkConf.checked)||
(dgReport__ctl5_chkConf.checked)||
(dgReport__ctl6_chkConf.checked)
)
)&&(
!(
confirm(
'You have not selected any DRs. '+
'Are you sure you want to submit change?'
)
)
)
){
return false;
}else{
return (
(typeof Page_ClientValidate == 'function')?
Page_ClientValidate():
false
);
}

- or as a single return statement:-


return (
(
(
(
(dgReport__ctl2_chkConf.checked)||
(dgReport__ctl3_chkConf.checked)||
(dgReport__ctl4_chkConf.checked)||
(dgReport__ctl5_chkConf.checked)||
(dgReport__ctl6_chkConf.checked)
)||(
confirm(
'You have not selected any DRs. '+
'Are you sure you want to submit change?'
)
)
)&&(
(typeof Page_ClientValidate == 'function')&&
Page_ClientValidate()
)
)||(
false
)
);

Richard.


But return statements are not your problem at all.

Richard.