1 //找出字符串中第一个不重复的字符 2 // firstUniqueChar("vdctdvc"); --> t 3 function firstUniqueChar(str){ 4   var str = str || "", 5       i = 0, 6       k = "", 7       _char = "", 8       charMap = {}, 9       result = {name: "",index: str.length};10   11   for(i=0;i<str.length;i++){12     _char = str.charAt(i);13     if(charMap[_char] != undefined){14       charMap[_char] = -1;15     }else{16       charMap[_char] = i;17     }18   }19   20   for(k in charMap){21     if(charMap[k]<0){22       continue;23     }24     if(result.index>charMap[k]){25       result.index = charMap[k];26       result.name = k;27     }28   }29   30   return result.name;31 }