如何使用JavaScript中的变量动态访问对象属性？

Question

I'm trying to filter data from JSON in JavaScript.

I define a variable a . I want the property of whatever value a is equal to (not item.a ). So far I've been unable to find a way of doing it.

Everything else is working correctly because when I changed it to a specific entry (item.date for example) it works fine. I cannot figure out the correct syntax.

while(i< elements.length){
    var a=elements[i].id;
    if(elements[i].name == 'targetfeild'){
      $(elements[i]).val($.map(result,function(item){var test = elements[i].id;return item.a;}));
    }
    i++;
}

Answer 1

尝试item[a] ，也可以通过这种方式访问​​javascript对象。