remove a string from within a string

[soni29]

hi,
how can i remove a string from an existing string in javascript. i
have a textbox in a form and want to make sure that when the user
clicks a button that certain words are moved, like all instances of
"hello" should be taken out of the text the user typed in the textbox.
any ideas?

thank you.

[Andrew Urquhart]

Re: remove a string from within a string

*soni29* wrote:[color=blue]
> hi,
> how can i remove a string from an existing string in javascript. i
> have a textbox in a form and want to make sure that when the user
> clicks a button that certain words are moved, like all instances of
> "hello" should be taken out of the text the user typed in the textbox.
> any ideas?[/color]

An example of one method:

<script type="text/javascript">
var objCensorWords = new Array("ears", "feet", "navel");

function Censor(objForm, strElementName) {
if (objForm && objForm.element s[strElementName]) {
var objElement = objForm.element s[strElementName];
var strData = objElement.valu e;
for (var i=0; i<objCensorWord s.length; ++i) {
var objRE = new RegExp(objCenso rWords[i], "ig");
strData = strData.replace (objRE, "");
}
objElement.valu e = strData;
return true;
}
else {
alert("An error message");
}
return false;
}
</script>
<form action="page.ex t" method="post"
onsubmit="retur n Censor(this, 'mydata');">
<fieldset>
<legend>Examp le Form</legend>
<label for="id_mydata" >Your data:</label>
<textarea name="mydata" id="id_mydata" cols="20" rows="3">The King has
donkeys' ears</textarea>
<input type="submit" value="Submit">
</fieldset>
</form>

Might be enough to give you an idea of how to implement your own.
Turning off javascript will present a whole new problem. In this example
strings in the 'objCensorWords ' array would need to be escaped if they
contain special characters that could be interpretted by the regular
expression engine (unless you specifically wanted that behaviour).
--
Andrew Urquhart
- FAQ: www.jibbering.com/faq/
- Archive: www.google.com/groups?q=comp.lang.javascript
- Contact me: http://andrewu.co.uk/contact/

[Steve van Dongen]

Re: remove a string from within a string

"Andrew Urquhart" <useWebsiteInSi gnatureToReply@ spam.invalid> wrote:
[color=blue]
>*soni29* wrote:[color=green]
>> hi,
>> how can i remove a string from an existing string in javascript. i
>> have a textbox in a form and want to make sure that when the user
>> clicks a button that certain words are moved, like all instances of
>> "hello" should be taken out of the text the user typed in the textbox.
>> any ideas?[/color]
>
>An example of one method:
>
><script type="text/javascript">
>var objCensorWords = new Array("ears", "feet", "navel");
>
>function Censor(objForm, strElementName) {
> if (objForm && objForm.element s[strElementName]) {
> var objElement = objForm.element s[strElementName];
> var strData = objElement.valu e;
> for (var i=0; i<objCensorWord s.length; ++i) {
> var objRE = new RegExp(objCenso rWords[i], "ig");[/color]

That should likely be
var objRE = new RegExp("\b" + objCensorWords[i] + "\b", "ig");
so that you only match it if word boundaries exist on both sides.

Regards,
Steve

[rh]

Re: remove a string from within a string

"Andrew Urquhart" wrote:[color=blue]
> *soni29* wrote:[color=green]
> > hi,
> > how can i remove a string from an existing string in javascript. i
> > have a textbox in a form and want to make sure that when the user
> > clicks a button that certain words are moved, like all instances of
> > "hello" should be taken out of the text the user typed in the textbox.
> > any ideas?[/color]
>
> An example of one method:
>
> <script type="text/javascript">
> var objCensorWords = new Array("ears", "feet", "navel");
>
> function Censor(objForm, strElementName) {
> if (objForm && objForm.element s[strElementName]) {
> var objElement = objForm.element s[strElementName];
> var strData = objElement.valu e;
> for (var i=0; i<objCensorWord s.length; ++i) {
> var objRE = new RegExp(objCenso rWords[i], "ig");
> strData = strData.replace (objRE, "");[/color]

As a note, when in possession of a set of alternates in an array, it's
often more efficient to generate the RegExp as, for example:

re = new RegExp("\\b("+o bjCensorWords.j oin("|")+")\\b" ,"ig")

thereby eliminating the need for a loop of repeated generation of
RegExps and their application to the string. Such a change will bury
the execution within standard regular expression processing.

../rh