扁平化数据``` ```r aa = [].concat.apply([], filter_item.map(item

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title></title>
</head>
<body>
<script type="text/javascript">
    
var filter_item =  [
        {
            defaultId: [1, 5],
            items: [
                {display: '我是', id: 1},
                {display: '我是5', id: 5}
            ]
        },
        {
            defaultId: [2],
            items: [
                {display: '我是222', id: 2} 
            ]
        },
        {
            defaultId: ['all', 12],
            items: [
                {display: '我是333', id: 'all'},
                {display: '我333', id: 12},
                {display: '我是333', id: 15} 
            ]
        }
    ]

var aa = [].concat.apply([], filter_item.map(item => {
    return item.items.filter(item2 => {
        return item2.id != 'all' && item.defaultId.indexOf(item2.id) != -1
    })
}));
console.log(aa)
</script>
</body>
</html>