javascript - jQuery:如果数组中存在键，则获取值

Question

我试图查看某个键是否存在于数组中，如果存在，则返回它的值:

if(jQuery.inArray(live_ids.grade, item.SizePrice) !== -1) {

    console.log(item.SizePrice);

}

这将返回:

{"8":"15.00","7":"20.00","1":"6.00","6":"11.00","2":"7.00","3":"8.00","4":"9.00","5":"10.00","11":"20.00","9":"10.00","10":"15.00","13":""}

现在，live_ids.grade = 9，所以我希望能够返回 10.00...我该怎么做？

Answer 1

这里检查数字是否在 obj 中，然后执行 else 显示错误。

var obj = {
    "8":"15.00",
    "7":"20.00",
    "1":"6.00",
    "6":"11.00",
    "2":"7.00",
    "3":"8.00",
    "4":"9.00",
    "5":"10.00",
    "11":"20.00",
    "9":"10.00",
    "10":"15.00",
    "13":""
};

var number = 9;

if(number in obj){
    alert(obj[number])
} else {
    alert("This number does not exists")
}