various useful as3 functions

useful_functions.as

// tinting
var colorTransform : ColorTransform = bmp.transform.colorTransform;
colorTransform.color = 0x3b1c4d;
bmp.transform.colorTransform = colorTransform;

// get URL of page where swf is embedded
function get currentURL():String
{
    var url:String;
    if (ExternalInterface.available) {
        return ExternalInterface.call("window.location.href");
    }
    return url;
}

// actionscript hates utf8
public static function encodeUTF8 (text:String):String {
    var a:uint, n:uint, A:uint;
    var utf:String;
    utf = "";
    A = text.length;
 
    for (a = 0; a < A; a++) {
        n = text.charCodeAt (a);
        if (n < 128) {
            utf += String.fromCharCode (n);
        } else if ((n > 127) && (n < 2048)) {
            utf += String.fromCharCode ((n >> 6) | 192);
            utf += String.fromCharCode ((n & 63) | 128);
        } else {
            utf += String.fromCharCode ((n >> 12) | 224);
            utf += String.fromCharCode (((n >> 6) & 63) | 128);
            utf += String.fromCharCode ((n & 63) | 128);
        }
    }
    return utf;
}

// PHP’s html_strip_tags
public static function stripHtmlTags(html:String, tags:String = ""):String
{
    var tagsToBeKept:Array = new Array();
    if (tags.length > 0)
        tagsToBeKept = tags.split(new RegExp("\\s*,\\s*"));
 
    var tagsToKeep:Array = new Array();
    for (var i:int = 0; i < tagsToBeKept.length; i++)
    {
        if (tagsToBeKept[i] != null && tagsToBeKept[i] != "")
            tagsToKeep.push(tagsToBeKept[i]);
    }
 
    var toBeRemoved:Array = new Array();
    var tagRegExp:RegExp = new RegExp("<([^>\\s]+)(\\s[^>]+)*>", "g");
 
    var foundedStrings:Array = html.match(tagRegExp);
    for (i = 0; i < foundedStrings.length; i++)
    {
        var tagFlag:Boolean = false;
        if (tagsToKeep != null)
        {
            for (var j:int = 0; j < tagsToKeep.length; j++)
            {
                var tmpRegExp:RegExp = new RegExp("<\/?" + tagsToKeep[j] + "( [^<>]*)*>", "i");
                var tmpStr:String = foundedStrings[i] as String;
                if (tmpStr.search(tmpRegExp) != -1)
                    tagFlag = true;
            }
        }
        if (!tagFlag)
            toBeRemoved.push(foundedStrings[i]);
    }
    for (i = 0; i < toBeRemoved.length; i++)
    {
        var tmpRE:RegExp = new RegExp("([\+\*\$\/])","g");
        var tmpRemRE:RegExp = new RegExp((toBeRemoved[i] as String).replace(tmpRE, "\\$1"),"g");
        html = html.replace(tmpRemRE, "");
    }
    return html;
}

/*
A slug is usually a few words with each word separated by a delimiting character, usually an underscore or hyphen. A slugified version of the string "10 Tips to a Better Life!" would be "10-tips-to-a-better-life".
*/
function slugify(string:String):String
{
    const pattern1:RegExp = /[^\w- ]/g; // Matches anything except word characters, space and -
    const pattern2:RegExp = / +/g; // Matches one or more space characters
    var s:String = string;
    return s.replace(pattern1, "").replace(pattern2, "-").toLowerCase();
}

// strip http
function stripHttp(string:String, stripWWW:Boolean = false):String
{
    var s:String = string;
    var regexp:RegExp = new RegExp(!stripWWW ? "https*:\/\/" : "https*:\/\/(www\.)*", "ig");
    return s.replace(regexp, "");
}

// strip xml namespace
function stripXMLNamespaces(xml:XML):XML
{
    var s:String = xml.toString();
    var pattern1:RegExp = /\s*xmlns[^\'\"]*=[\'\"][^\'\"]*[\'\"]/gi;
    s = s.replace(pattern1, "");
    var pattern2:RegExp = /&lt;[\/]{0,1}(\w+:).*?&gt;/i;
    while(pattern2.test(s)) {
        s = s.replace(pattern2.exec(s)[1], "");
    }
    return XML(s);
}

// email validation
public static function validateEmail(email:String):Boolean {
    var emailExpression:RegExp = /^[a-z][\w.-]+@\w[\w.-]+\.[\w.-]*[a-z][a-z]$/i;
    return emailExpression.test(email);
}

// position objects in grid
for (var i:uint = 0; i < 20; i++)
{
    var displayObject:MyDisplayObject = new MyDisplayObject();
    displayObject.x = displayObject.width * ( i % 5 );
    displayObject.y = displayObject.height * Math.floor( i / 5 );
    addChild(displayObject);
}

// Round the Positional Values of a DisplayObjectContainer and its Children
function roundPositions(displayObjectContainer:DisplayObjectContainer):void
{
    if (!(displayObjectContainer is Stage)) {
        displayObjectContainer.x = Math.round(displayObjectContainer.x);
        displayObjectContainer.y = Math.round(displayObjectContainer.y);
    }
    for (var i:uint = 0; i < displayObjectContainer.numChildren; i++) {
        var child:DisplayObject = displayObjectContainer.getChildAt(i);
        if (child is DisplayObjectContainer) {
            roundPositions(child as DisplayObjectContainer);
        } else {
            child.x = Math.round(child.x);
            child.y = Math.round(child.y);
        }
    }
}