javascript RGB转换为HEX十六进制

 1 Sys.rgbToHex = function(color) {
 2         var arr = [],
 3             strHex;
 4         if (/^(rgb|RGB)/.test (color)) {
 5             arr = color.replace(/(?:\(|\)|rgb|RGB)*/g, "").split(",");
 6             strHex = ‘#‘ + ((1 << 24) + (arr[0] << 16) + (arr[1] << 8) + parseInt(arr[2])).toString(16).substr(1);
 7         } else {
 8             strHex = color;
 9         }
10         return strHex;
11 };