var arr1 = [12,'ss','sdd','sdd','kk'];
function unique(array){
var o = {},b = [];
for(var i=0;i<array.length;i++){
if(!o[array[i]]){
b.push(array[i]);
o[array[i]] = true;
}
}
return b;
}
unique(arr1) //It works fine .output [12,'ss','sdd','kk']
but,it has some issues on arr2 below:
var arr2 = [12,'ss','sdd','sdd','kk','12'];//output [12,'ss','sdd','kk']
does it make wrong?I think it should output [12,'ss','sdd','kk','12'],can we fixed this promble?
Key names are always converted to a string. I recommend to use Array.prototype.indexOf in order to check whether an array entry is unique or not. The indexOf method also behaves correctly regarding objects[1].
Demo: http://jsfiddle.net/YE9jx/
function unique(array){
var b = [];
for(var i=0; i<array.length; i++){
if(b.indexOf(array[i]) == -1) b.push(array[i]);
}
return b;
}
[1] The correct behaviour is: Different if the object references are different:
var obj1 = [1,2];
var obj2 = [1,2];
unique([obj1, obj2]); //[[1,2], [1,2]] // Because they're different arrays
unique([obj1, obj1]); //[[1,2]] // Because both elements are obj1
Array.indexOf() - if you want to allow for this you can add the code shown here at MDN.When the number 12 was used as a dictionary key, it was promoted to string, making it the same key as the last string '12'
var i=0should be a semicolon.