Full code after the jump.

View MXML

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/04/21/looping-over-each-item-in-an-array-in-actionscript-30/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white"
        initialize="init();">

    <mx:Script>
        <![CDATA[
            import mx.utils.ObjectUtil;

            private function init():void {
                beforeTextArea.text = ObjectUtil.toString(dp);
                dp.forEach(forEach_test);
                dataGrid.dataProvider = dp;
                afterTextArea.text = ObjectUtil.toString(dp);
            }

            private function forEach_test(element:*, index:int, arr:Array):void {
                element.lbl = element.name + " (" + element.abbr + ")";
                element.idx = index;
            }
        ]]>
    </mx:Script>

    <mx:Array id="dp">
        <mx:Object name="Baltimore Orioles" abbr="BAL" />
        <mx:Object name="Boston Red Sox" abbr="BOS" />
        <mx:Object name="Chicago White Sox" abbr="CWS" />
        <mx:Object name="Cleveland Indians" abbr="CLE" />
        <mx:Object name="Detroit Tigers" abbr="DET" />
        <mx:Object name="Kansas City Royals" abbr="KC" />
        <mx:Object name="Los Angeles Angels of Anaheim" abbr="LAA" />
        <mx:Object name="Minnesota Twins" abbr="MIN" />
        <mx:Object name="New York Yankees" abbr="NYY" />
        <mx:Object name="Oakland Athletics" abbr="OAK" />
        <mx:Object name="Seattle Mariners" abbr="SEA" />
        <mx:Object name="Tampa Bay Devil Rays" abbr="TB" />
        <mx:Object name="Texas Rangers" abbr="TEX" />
        <mx:Object name="Toronto Blue Jays" abbr="TOR" />
    </mx:Array>

    <mx:DataGrid id="dataGrid"
            verticalScrollPolicy="on"
            width="100%">
        <mx:columns>
            <mx:DataGridColumn dataField="name" />
            <mx:DataGridColumn dataField="abbr" width="80" />
            <mx:DataGridColumn dataField="lbl" />
            <mx:DataGridColumn dataField="idx" width="40" textAlign="right" />
        </mx:columns>
    </mx:DataGrid>

    <mx:Form width="100%" height="100%">
        <mx:FormItem label="Before:" width="100%" height="50%">
            <mx:TextArea id="beforeTextArea"
                    editable="false"
                    wordWrap="false"
                    width="100%"
                    height="100%" />
        </mx:FormItem>
        <mx:FormItem label="After:" width="100%" height="50%">
            <mx:TextArea id="afterTextArea"
                    editable="false"
                    wordWrap="false"
                    width="100%"
                    height="100%" />
        </mx:FormItem>
    </mx:Form>

</mx:Application>

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