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Want to construct a function instead of the code for onkeyup

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  Want to construct a function instead of the code for onkeyup "Tony Johansson" <johansson.andersson@telia.com> - 2013-01-16 22:51 +0100
    Re: Want to construct a function instead of the code for onkeyup Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-01-16 23:29 +0100
      Re: Want to construct a function instead of the code for onkeyup "Tony" <tony.johansson@inport.com> - 2013-01-17 09:10 +0100
        Re: Want to construct a function instead of the code for onkeyup "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-01-17 15:40 +0100
      Re: Want to construct a function instead of the code for onkeyup "Tony" <tony.johansson@inport.com> - 2013-01-17 09:23 +0100

#18116 — Want to construct a function instead of the code for onkeyup

Hello!

How should I write a function if I want to move the code 
that is executed for onkeyup ?

<input type="text"  name="depthBow" id="txtDepthBow" size="20"
   onkeyup="if (/[^0-9\.,]/g.test(this.value))
   this.value = this.value.replace(/[^0-9\.,]/g,'')" />

//Tony

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#18117

Tony Johansson wrote:

> How should I write a function if I want to move the code
> that is executed for onkeyup ?
> 
> <input type="text"  name="depthBow" id="txtDepthBow" size="20"
>    onkeyup="if (/[^0-9\.,]/g.test(this.value))
>    this.value = this.value.replace(/[^0-9\.,]/g,'')" />

You should pass the “this” value, here a DOM object reference, as argument 
to the function:

<https://developer.mozilla.org/en-
US/docs/JavaScript/Reference/Functions_and_function_scope>

<http://jibbering.com/faq/>
<http://PointedEars.de/faq>

And do not use the RegExp flag “g(lobal)” with RegExp.prototype.test(), as 
it is a wrapper around RegExp.prototype.exec() [ES 5.1, § 15.10.6.3]:

  var rx = /x/g;

  /* true */
  rx.test("x")
  
  /* false */
  rx.test("x")

  /* true */
  rx.test("x")

That another /RegularExpressionLiteral/ creates a new RegExp object is a 
change from ECMAScript Ed. 3 to 5 [Annex E]; do not rely on it unless you 
know what you are doing.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

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#18121

I have now replaced the code for onkeyup with a function. See below.
The function name is RemoveInvalidCharacters and it is listed below. When I 
call this function I get the following error
which is transladed from swedish

Runtime error in javascript: It's not possible to get properties replace for 
a reference that is undefined or null

So why do I get this error if I keep the code in onkeyup it works fine ?

function RemoveInvalidCharacters()
        {
            if (/[^0-9\.,]/g.test(this.value))
            {
                // Filter non-digits from input value.
                this.value = this.value.replace(/[^0-9\.,]/g, '');
            }
        }


<input type="text"  name="depthSteern" id="txtDepthSteern" size="21" 
onkeyup="if (/[^0-9\.,]/g.test(this.value)) this.value = 
this.value.replace(/[^0-9\.,]/g,'')" />
<input type="text"  name="depthBow" id="txtDepthBow" size="20" 
onkeyup="RemoveInvalidCharacters()" />

"Thomas 'PointedEars' Lahn"  wrote in message 
news:37748651.8yA5jalnsy@PointedEars.de...

Tony Johansson wrote:

> How should I write a function if I want to move the code
> that is executed for onkeyup ?
>
> <input type="text"  name="depthBow" id="txtDepthBow" size="20"
>    onkeyup="if (/[^0-9\.,]/g.test(this.value))
>    this.value = this.value.replace(/[^0-9\.,]/g,'')" />

You should pass the “this” value, here a DOM object reference, as argument
to the function:

<https://developer.mozilla.org/en-
US/docs/JavaScript/Reference/Functions_and_function_scope>

<http://jibbering.com/faq/>
<http://PointedEars.de/faq>

And do not use the RegExp flag “g(lobal)” with RegExp.prototype.test(), as
it is a wrapper around RegExp.prototype.exec() [ES 5.1, § 15.10.6.3]:

  var rx = /x/g;

  /* true */
  rx.test("x")

  /* false */
  rx.test("x")

  /* true */
  rx.test("x")

That another /RegularExpressionLiteral/ creates a new RegExp object is a
change from ECMAScript Ed. 3 to 5 [Annex E]; do not rely on it unless you
know what you are doing.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail. 

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#18125

Tony wrote on 17 jan 2013 in comp.lang.javascript:

> function RemoveInvalidCharacters()
>         {
>             if (/[^0-9\.,]/g.test(this.value))
>             {
>                 // Filter non-digits from input value.
>                 this.value = this.value.replace(/[^0-9\.,]/g, '');
>             }
>         }

= The "this" does not automagically follow you into the function. You will 
have to send the object as a function parameter.

= You do not have to test first to remove characters,
as only characters that are present can be removed.
Stands to reason, doesn't it?

= [\d] is the same as [0-9]

= [.] does not need to be escaped.

Try this [better don't, read on]:

=============================
<input onkeyup = 'removeInvalidCharacters(this)'


function removeInvalidCharacters(x) {
    x.value = x.value.replace(/[^\d.,]/g, '');
};
=============================

Even then onkeyup will not work as expected on all browsers, I believe I 
remember, as some browser input value will only update when the cursor 
leaves the input. Not tested however. And your user does not like to have 
dead keys on his/her keyboard, (s)he will hate you for that. And perhaps 
the character cursor will jump to the start when you replace the input 
value, also not something to make your user happy.

You are making mistakes many of us made in the last century. No matter, 
try to learn from it.

I would suggest testing or correcting the values onblur or even better on 
form submit.



-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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#18122

It works now!

//Tony

"Thomas 'PointedEars' Lahn"  wrote in message 
news:37748651.8yA5jalnsy@PointedEars.de...

Tony Johansson wrote:

> How should I write a function if I want to move the code
> that is executed for onkeyup ?
>
> <input type="text"  name="depthBow" id="txtDepthBow" size="20"
>    onkeyup="if (/[^0-9\.,]/g.test(this.value))
>    this.value = this.value.replace(/[^0-9\.,]/g,'')" />

You should pass the “this” value, here a DOM object reference, as argument
to the function:

<https://developer.mozilla.org/en-
US/docs/JavaScript/Reference/Functions_and_function_scope>

<http://jibbering.com/faq/>
<http://PointedEars.de/faq>

And do not use the RegExp flag “g(lobal)” with RegExp.prototype.test(), as
it is a wrapper around RegExp.prototype.exec() [ES 5.1, § 15.10.6.3]:

  var rx = /x/g;

  /* true */
  rx.test("x")

  /* false */
  rx.test("x")

  /* true */
  rx.test("x")

That another /RegularExpressionLiteral/ creates a new RegExp object is a
change from ECMAScript Ed. 3 to 5 [Annex E]; do not rely on it unless you
know what you are doing.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail. 

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