get style from jQuery Object

heaven_1025

Hi,
I'm new guy for using sahi. and I want to know how to get style from jQuery Object.

I want to get background Color from following object, but the backgroundColor is determined by class.
when I used function: _style($divObj, 'backgroundColor') or _style($divObj, 'background-color'), it returns null.
So I used _eval() funtion to get css attribute from jQuery Object, and It can return backgroundColor like this: rgb(59,75,91). but when I pass the object "$var1" to rgbToHexUpCase() function, it can not finish the string connection using character "+", concat function, and array.join() fucntion. and It always return : //#NANNANNAN

so, my question:
1. why is #NANNANNAN after concating with each element?
2. has any better ideas for getting css from class?
3. the detail instructions about _eval() function:

html:
<div id="__button202" data--ui="__button202" data--automation-id="multiTab-B-nonProspectUser" class="ClientMTabButton ClientMTabButtonIconVisible ClientMTabButtonSelected MBarChild">

my sahi code:

var $Obj=_byXPath("//div[@data-automation-id='multiTab-B-nonProspectUser' and contains(@class,'ClientMTabButtonSelected')]");
var $var1=_eval("$(" + $Obj + ").css('backgroundColor')"); //it can return background Color like this: rgb(59,75,91)
rgbToHexUpCase($var1);

function rgbToHexUpCase($rgbColor){
    _log("[rgbToHexUpCase], input parameter:"+$rgbColor+", type:"+typeof($rgbColor));
    var $stop = $rgbColor.indexOf(")");
    var $result, $tmp;
    if($rgbColor.indexOf("rgba")>-1){
        $tmp = $rgbColor.substring(5, $stop);
    }else{
        $tmp = $rgbColor.substring(4, $stop);
    }
    $result = $tmp.split(",",3);
   var $r=rgbUCase($result[0].trim()); //3B
   var $g=rgbUCase($result[1].trim());//4B
   var $b=rgbUCase($result[2].trim());//5B

    var $rtn1="#"+$r+$g+$b;
    _log("[rgbToHexUpCase], value:" + $rtn1); //#NANNANNAN
   return $rtn1;
}

function rgbUCase($rgbValue){
  _log("[rgbUCase], input param:" + $rgbValue + ", type:" + typeof($rgbValue));
  var $hex = Number($rgbValue).toString(16).toUpperCase();
	if($hex.length <2){
		$hex = "0"+ $hex;
	}
	return $hex;
}