Yet another validate number ??? Allow negative and period (-.5) etc.

[KathyB]

Hi,

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

function ValidateSave(fo rmRef,fieldName ,min,max) {
var formField = formRef.element s[fieldName];
if (!/^\d+(\.\d+)?$/.test(formField .value)) {
alert('Invalid entry...please try again!');
formField.focus ();
formField.selec t();
return false;
}

[Janwillem Borleffs]

"KathyB" <Ka**********@a ttbi.com> schreef in bericht
news:75******** *************** **@posting.goog le.com...

Hi,

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

You cand do this without regular expressions with the isFinite function:

var num = -.5;
alert(isFinite( num)); // Alerts `true`
JW

[Dr John Stockton]

JRS: In article <75************ *************@p osting.google.c om>, seen
in news:comp.lang. javascript, KathyB <Ka**********@a ttbi.com> posted at
Fri, 19 Dec 2003 16:22:53 :-

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

function ValidateSave(fo rmRef,fieldName ,min,max) {
var formField = formRef.element s[fieldName];
if (!/^\d+(\.\d+)?$/.test(formField .value)) {
alert('Inval id entry...please try again!');
formField.focu s();
formField.sele ct();
return false;
}

You should indent your code to show its structure. Hard-to-read code is
likely to be ignored.

You should not allow a decimal point with no digit before it; nor with
no digit after. Such constructions are liable to be mistakes. Your
words allow it, but not your code. If a - sign is allowed, a + sign
should be allowed and might be mandated.

You have: Bad = !/^\d+(\.\d+)?$/.test(formField .value)
You need: Bad = !/^(\+|-)?\d+(\.\d+)?$/.test(formField .value)

See <URL:http://www.merlyn.demo n.co.uk/js-valid.htm>.

--
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[@SM]

KathyB a ecrit :

Hi,

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

function ValidateSave(fo rmRef,fieldName ,min,max) {

with(formRef[fielName]){
if(value.parseF loat()!=value || value<min || value>max)
{
alert('Invalid entry...please try again!');
focus();
select();
return false;
}
}
}

[Dr John Stockton]

JRS: In article <3F************ ***@wanadoo.fr> , seen in
news:comp.lang. javascript, @SM <st************ **@wanadoo.fr> posted at
Sun, 21 Dec 2003 05:34:12 :-

KathyB a ecrit :

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

function ValidateSave(fo rmRef,fieldName ,min,max) {

with(formRef[fielName]){
if(value.parseF loat()!=value || value<min || value>max)
{
alert('Invalid entry...please try again!');
focus();
select();
return false;
}
}
}

On which system did you test that? In MSIE4, strings appear not to have
a parseFloat method, and parseFloat is a global function.

When answering, please leave a gap, and do not start on a line which
already has a quote mark.

--
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[Kathy Burke]

John, used strictly with IE5.5 on an intranet.

Kathy

*** Sent via Developersdex http://www.developersdex.com ***
Don't just participate in USENET...get rewarded for it!

[Dr John Stockton]

JRS: In article <3f************ *********@news. frii.net>, seen in
news:comp.lang. javascript, Kathy Burke <ka**********@a ttbi.com> posted
at Mon, 22 Dec 2003 00:59:55 :-

John, used strictly with IE5.5 on an intranet.

That seems irrelevant to the question that I was asking about @SM's
testing.
--
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[KathyB]

John,

Using what you kindly provided:

You have: Bad = !/^\d+(\.\d+)?$/.test(formField .value)
You need: Bad = !/^(\+|-)?\d+(\.\d+)?$/.test(formField .value)

....validates ok for negative whole numbers but not for -.5 etc.
(invalid entry message). This works great if the user remembers to put
-0.5, but not if they leave off the zero and enter -.5 -- any way
around this? Silly, I know, but I have quite the user community!

Thanks again, Kathy

p.s. thought you're other question was directed at me...thought it was
strange :-) but I answered it anyway!

Dr John Stockton <sp**@merlyn.de mon.co.uk> wrote in message news:<1w******* *******@merlyn. demon.co.uk>...

JRS: In article <75************ *************@p osting.google.c om>, seen
in news:comp.lang. javascript, KathyB <Ka**********@a ttbi.com> posted at
Fri, 19 Dec 2003 16:22:53 :-

I just can't get this quite right. I use the following function to
validate a user entry. I need to allow negative numbers including
those with decimals (e.g., -.5). The following allows the decimals but
not the negative. Any help appreciated...a s always. Thanks -- Kathy

function ValidateSave(fo rmRef,fieldName ,min,max) {
var formField = formRef.element s[fieldName];
if (!/^\d+(\.\d+)?$/.test(formField .value)) {
alert('Inval id entry...please try again!');
formField.focu s();
formField.sele ct();
return false;
}

You should indent your code to show its structure. Hard-to-read code is
likely to be ignored.

You should not allow a decimal point with no digit before it; nor with
no digit after. Such constructions are liable to be mistakes. Your
words allow it, but not your code. If a - sign is allowed, a + sign
should be allowed and might be mandated.

You have: Bad = !/^\d+(\.\d+)?$/.test(formField .value)
You need: Bad = !/^(\+|-)?\d+(\.\d+)?$/.test(formField .value)

See <URL:http://www.merlyn.demo n.co.uk/js-valid.htm>.

[Dr John Stockton]

JRS: In article <75************ **************@ posting.google. com>, seen
in news:comp.lang. javascript, KathyB <Ka**********@a ttbi.com> posted at
Mon, 22 Dec 2003 16:35:01 :-

You have: Bad = !/^\d+(\.\d+)?$/.test(formField .value)
You need: Bad = !/^(\+|-)?\d+(\.\d+)?$/.test(formField .value)

...validates ok for negative whole numbers but not for -.5 etc.
(invalid entry message). This works great if the user remembers to put
-0.5, but not if they leave off the zero and enter -.5 -- any way
around this? Silly, I know, but I have quite the user community!
Having a decimal point without a digit on each side is strongly
deprecated, because allowing it is too likely to lead to un-noticed
error. See, for example, SUNAMCO 87-1 (IUPAP-25), 1987 revision, by
Cohen & Giacomo, Section 1.3.2.; either it, or a successor, ought to be
on the Web somewhere. I decline to support breach of its
recommendation.
Dr John Stockton <sp**@merlyn.de mon.co.uk> wrote in message news:<1wZxAIAoH J5$Ew
[e-mail] n.co.uk>...

Responses should go AFTER trimmed quotes - see newsgroup FAQ.

--
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<URL:http://www.merlyn.demo n.co.uk/js-index.htm> jscr maths, dates, sources.
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[@SM]

Dr John Stockton a ecrit :

JRS: In article <3F************ ***@wanadoo.fr> , seen in
news:comp.lang. javascript, @SM <st************ **@wanadoo.fr> posted at
Sun, 21 Dec 2003 05:34:12 :-

function ValidateSave(fo rmRef,fieldName ,min,max) {with(formRef[fielName]){
if(value.parseF loat()!=value || value<min || value>max)
{
alert('Invalid entry...please try again!');
focus();
select();
return false;
}
}
}

On which system did you test that?

Never where !
In MSIE4, strings appear not to have
I've no more IE4 installed.
But ...
just don't tell him 'min' and 'max' are strings ! ! !
that's to say calling the function this way :
ValidateSave(th is,'myFieldName ',-.95,2.74)
a parseFloat method, and parseFloat is a global function.
Don't understand what you mean,
here, parseFloat is only used to test if the entry is a number

I've seen there was a little error in my code ! :-(
Here is something working fine (even with Mac IE5.0)

<html>
<script type="text/javascript"><!--
function ValidateSave(fo rmRef,fieldName ,min,max) {
with(formRef[fieldName]){
value=value.rep lace(',','.');
if(parseFloat(v alue)!=value || value<min || value>max)
{
alert('Invalid entry...please try again!');
focus();
select();
return false;
}
}
}
onload=setTimeo ut('document.fo rms[0][0].focus()',10);
// --></script>
<FORM ACTION="00.htm" METHOD=get TARGET="_blank"
onSubmit="retur n ValidateSave(th is,'TxtField',-.75,1.1)">
<INPUT TYPE=text NAME="TxtField" VALUE="">
<INPUT TYPE=submit VALUE="Submit">
<input type=button value="refresh" onclick="locati on=self.locatio n;">
</FORM>
</html>
When answering, please leave a gap, and do not start on a line which
already has a quote mark.

That's not very important ...

Note only that some systems use ',' isnteed of '.' as separator