SetPropertyFromJs

<div id="VisifireChart0">

<script type="text/javascript">  

        var vChart = new Visifire('SL.Visifire.Charts.xap',500,300);

        vChart.setDataUri("Sample1.xml");

         /* This event will be fired before loading the chart into

            Silverlight user-control. */

         vChart.preLoad = function(args)

         {

                /* First Chart Reference. If there are multiple charts in a

                   XAML file, array of chart references will be available as

                   an event argument, e.g. args[0], args[1], args[2] etc. */

                var chart = args[0];

                var ds = chart.Series[0];

                // String as brush.

 var brush1 = '<LinearGradientBrush  xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\"'  + 'EndPoint="0.5,1" StartPoint="0.5,0">'

+ '<GradientStop Color="#FF000000"/>'

+ '<GradientStop Color="#FFFFFFFF" Offset="1"/>'

+ '</LinearGradientBrush>';

 // Set Color of a DataSeries

 ds.SetPropertyFromJs("Color", brush1);

 // DataPoint reference

 var dataPoint = ds.DataPoints[0];

 // Set YValue of a DataPoint

 dataPoint.SetPropertyFromJs("YValue","10");

 // String as brush

 var brush2 = '<LinearGradientBrush  xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\"'

 +' EndPoint="0.5,1" StartPoint="0.5,0">'

 + '<GradientStop Color="#FF000000"/>'

 + '<GradientStop Color="#FFFFFFFF" Offset="1"/>'

 + '</LinearGradientBrush>';

 // Set Color of a DataPoint

 dataPoint.SetPropertyFromJs("Color", brush2);

        };

        vChart.render("VisifireChart0");

</script>

</div>