javascript - 设置数组中对象的属性

Question

我有一个对象的数组，如下所示:

manualInputHeaders = [
    {text: 'Store No', title: 'Enter Destination Store Number'},
    {text: 'Promise Date', title: 'Enter promise ship data', classes: {classAdditions: 'tooltipInput'}}
]

我正在尝试设置

manualInputHeaders[0].classes.classAdditions = 'setMe'

但是，chrome 控制台给出:

Uncaught TypeError: Cannot set property 'classAdditions' of undefined

如何设置Array中Object的属性？

Answer 1

您必须首先创建该对象(如果它尚不存在):

manualInputHeaders[0].classes = manualInputHeaders[0].classes || {};
manualInputHeaders[0].classes.classAdditions = 'setMe';