查询javascript对象数组中的唯一属性值的最佳方法是什么？

Question

在以下示例数组中查找"foo"的所有可能值的最佳(或最快)方法是什么.

var table = [
    {foo: 0, bar:"htns", stuff:123},
    {foo: 2, bar:"snhn", stuff:156},
    {foo: 5, bar:"trltw", stuff:45},
    {foo: 5, bar:"lrctm", stuff:564},
    //few thousand lines later
    {foo: 2596, bar:"cns", stuff:321},
    {foo: 2597, bar:"gcrl", stuff:741}
];

Answer 1

循环遍历数组并将值放在哈希(对象)中.它是一种O(n)算法.

var result = {};
for(var i=0; i<table.length; i++) {
    result[table[i].foo] = 1; //the value can be anything
}

//now read back the unique values
for (i in result) {
    if (result.hasOwnProperty(i)) { 
        console.log(i);
    }
}