RegExp for excluding special characters in a string.

Report · Apr 21, 2012

Hi All,

Im using Flex RegExpValidator. Can anyone suggest me the correct expression to validate this condition?....

I have tried this expression :----- /^[^///\/</>/?/*&]+$/...But in this it is also negating the alphabets.Also I have tried with opposite condition that in the String we should have alphabets and the expression is:-- ([a-z]|[A-Z]|[0-9]|[ ]|[-]|[_])*..... Please can anyone help me on this.

Thanks in advanced to all.

Munira

Report · Apr 23, 2012

maybe this will help you find the answer

http://stackoverflow.com/questions/756567/regular-expression-for-excluding-special-characters

Report · Apr 24, 2012

Hi ,

Thanks for your reply.I have tried this condition.

And got following result:--

If you give only alphabets with no special symbols.The expression is valid

that is what is my requiremnet.

If you give only special characters .Expression is invalid what is our

requiremnet.

But if you give mixed expression of Special symbols and alphanumeric

characters it is considering it as Valid .

iwr ote:

**
Re: RegExp for excluding special characters in a string. created by
spoboyle <http://forums.adobe.com/people/spoboyle> in Flex - View the
full discussion <http://forums.adobe.com/message/4354492#4354492

Report · Apr 24, 2012

did you use

var pattern:RegExp = /^[a-zA-Z0-9 -_]*$/;

or

var pattern:RegExp = /^[a-zA-Z0-9 \-_]*$/;

remember - needs to be escaped since it's used to indicate a range of values

Report · Apr 24, 2012

I have used these expressions ,but nothing worked properly with

RegExpValidator:--

/^[///\/</>/?/*&]+$/

^[a-zA-Z0-9_-]$

^[-_,A-Za-z0-9]$

Also I have tried with the expressions u have provided .But the same

problem occurs it Invalidates alphanumeric characters as well.

May be its RegExpValidator issue or some expression issue.

What I have noticed is that the negate character (^) is not considered as

negate.

Please assist me to get it resolved.

Thanks and Regards

Munira

Report · Apr 25, 2012

^ at the start is not a negate its a start of line character

^ within a [] is a negation

Report · Apr 25, 2012

Yes you are correct ,but I have tried this with single special character

say

Then also its not negating it ...

Can you please put some light on it.

Thanks and Regards

Munira

Report · Apr 26, 2012

sorry but you are posting things back that do not make any sense

what do you mean with the below comment?

munira06 wrote:
Yes you are correct ,but I have tried this with single special character
say
Re: RegExp for excluding special characters in a string.

here is a sample app taken from the live docs

using ^[a-zA-Z0-9 \-_]*$ as the regex accepts all characters from a-z, A-Z, 0-9 - [space] and_

run the example tell me what regex you are using and what test strings fail when they should pass or pass when they should fail

<?xml version="1.0" encoding="utf-8"?>
<!-- Simple example to demonstrate the RegExpValidator. -->
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/mx">
    <fx:Script>
        <![CDATA[
            import mx.events.ValidationResultEvent;
            import mx.validators.*;
            // Write the results to the 
            private function handleResult(eventObj:ValidationResultEvent):void {
                if (eventObj.type == ValidationResultEvent.VALID) {
                    // For valid events, the results Array contains
                    // RegExpValidationResult objects.
                    var xResult:RegExpValidationResult;
                    reResults.text = "";
                    for (var i:uint = 0; i < eventObj.results.length; i++) {
                        xResult = eventObj.results;
                        reResults.text=reResults.text + xResult.matchedIndex + " " + xResult.matchedString + "\n";
                    }
                } else {
                    reResults.text = "";
                }
            }
        ]]>
    </fx:Script>
    <fx:Declarations>
        <mx:RegExpValidator id="regExpV" 
                source="{regex_text}" property="text" 
                flags="g" expression="{regex.text}" 
                valid="handleResult(event)"
                invalid="handleResult(event)"
                trigger="{myButton}"
                triggerEvent="click"/>
    </fx:Declarations>
    <s:Panel title="RegExpValidator Example"
            width="75%" height="75%"
            horizontalCenter="0" verticalCenter="0">
        <s:VGroup left="10" right="10" top="10" bottom="10">
            <s:Label width="100%" text="Instructions:"/>
            <s:Label width="100%" text="1. Enter text to search. By default, enter  a string containing the letters ABC in sequence followed by any digit."/>
            <s:Label width="100%" text="2. Enter the regular expression. By default, enter ABC\d."/>
            <s:Label width="100%" text="3. Click the Button control to trigger the validation."/>
            <s:Label width="100%" text="4. The results show the index in the text where the matching pattern begins, and the matching pattern. "/>
            <mx:Form>
                <mx:FormItem label="Enter text:">
                    <s:TextInput id="regex_text" text="xxxxABC4xxx" width="100%"/>
                </mx:FormItem>
                <mx:FormItem label="Enter regular expression:">
                    <s:TextInput id="regex" text="ABC\d" width="100%"/>
                </mx:FormItem>
                <mx:FormItem label="Results:">
                    <s:TextInput id="reResults" width="100%"/>
                </mx:FormItem>
                <mx:FormItem >
                    <s:Button id="myButton" label="Validate"/>
                </mx:FormItem>
            </mx:Form>
        </s:VGroup>
    </s:Panel>
</s:Application>

Report · Apr 26, 2012

I have tried with your expression:--

But some time it shows invalid msg for special characters .

Not all time you give .

You can try with following code:--

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"

xmlns:s="library://ns.adobe.com/flex/spark"

xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600"

xmlns:local="*">

<fx:Script>

<![CDATA[

private var exp106:String = "^[a-zA-Z0-9 \-_]*$"

private function button1_clickHandler(event:MouseEvent):void{

regValidator.validate();

}

]]>

</fx:Script>

<fx:Declarations>

<mx:RegExpValidator id="regValidator" expression=""

noMatchError="Not valid" source=""

flags="g" property="text" required="true" requiredFieldError="Please enter

string" />

</fx:Declarations>

<mx:VBox>

<s:TextInput id="textBox" />

<s:Button label="validate" click="button1_clickHandler(event)" />

</mx:VBox>

</s:Application

Report · Apr 26, 2012

it would be helpful if you can stop posting Re: RegExp for excluding special characters in a string. in the middle of all you posts

and tell me what test strings are failing when they should pass or pass when they should fail

Report · Apr 26, 2012

once I had worked out how to make your code compile

I had to make some small change for some reason I can't get the expression to bind to exp106 but if I hard code the regex into your validator I cna't find any cases that doesn't wrk as intended.

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
   xmlns:s="library://ns.adobe.com/flex/spark"
   xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600" xmlns:local="*">
          <fx:Script>
          <![CDATA[
                    [Bindable]
                    private var exp106:String = "^[a-zA-Z0-9 \-_]*$";
  
                    private function button1_clickHandler(event:MouseEvent):void{
                              regValidator.validate();
                    }
          ]]>
          </fx:Script>
          <fx:Declarations>
          <!-- Place non-visual elements (e.g., services, value objects) here -->
                    <mx:RegExpValidator id="regValidator" 
                              expression="^[a-zA-Z0-9 \-_]*$" source="{textBox}" 
                              flags="g" property="text" required="true" requiredFieldError="Please enter string"/>
          </fx:Declarations>
  
          <mx:VBox>
                    <s:TextInput id="textBox" />
                    <s:Button label="validate" click="button1_clickHandler(event)" />
          </mx:VBox>
</s:Application>

Report · Apr 26, 2012

Hi

Thanks for the help.

I have tried the expression ^[a-zA-Z0-9 \-_]*$

And this is working as per requirements but when it is declared within mxml

tag of RegExpValidator.

Actually I have to use this condition at many places and that's why I have

marked it as "Static Const".

So please tell me a way by which I can avoid the problem of "not properly

working of this expression when taken as variable"..

It is working when :--

<mx:RegExpValidator id="regExpValidator"

source="" property="text" expression="^[a-zA-Z0-9 \-_]*$" noMatchError="" enabled="false"/> But it is not working properly when the condition:-- <mx:RegExpValidator id="regExpValidator" source="" property="text"

expression="{TCConstants.TEMPLATE_NAME_REGULAR_EXPRESSION}"

noMatchError=""

enabled="false"/>

Thank you once again...

Report · Apr 27, 2012

I found a way to move the regex into a variable

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
   xmlns:s="library://ns.adobe.com/flex/spark"
   xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600" xmlns:local="*">
          <fx:Script>
          <![CDATA[
                    private static const exp106:RegExp = /^[a-zA-Z0-9 \-_]*$/;
  
                    private function button1_clickHandler(event:MouseEvent):void{
                              regValidator.validate();
                    }
          ]]>
          </fx:Script>
          <fx:Declarations>
          <!-- Place non-visual elements (e.g., services, value objects) here -->
                    <mx:RegExpValidator id="regValidator" 
                              expression="{exp106.source}" source="{textBox}" 
                              flags="g" property="text" required="true" requiredFieldError="Please enter string"/>
          </fx:Declarations>
  
          <mx:VBox>
                    <s:TextInput id="textBox" />
                    <s:Button label="validate" click="button1_clickHandler(event)" />
          </mx:VBox>
</s:Application>

Report · Apr 27, 2012

Hey many many thanks for solving this issue.

Once again thanks to you a lot

Regards

Munira