javascript去除数组重复项

function dist(){  var s = ["a","ba","a","c"];     var arr = [], map = {};  for(var i=0; i<s.length; i++){       var n = s[i];       if(!map.hasOwnProperty(n)){           map[n] = true;           arr.push(n);       }     }    alert(arr);}function dist1(){var array=[2.3,2.3,"a","b","b",true,true,true,false,1,0,undefined,null];   for(var i=0;i<array.length;i++){       for(var j=i+1;j<array.length;j++){          if(array[j]===array[i]) {              array.splice(j,1);              j--;            }                 }   }   alert(array);}