我有一个如下格式的结构，我需要将新属性$User.Concerts.UserTitle的值设置为$User.Concerts.User.Title
我尝试过类似于“用户.音乐会.用户标题”的内容：“$User.Concerts.Users.Title”。这会将新属性设置为数组而不是字符串。如何修复？

{
    "Id": "Id1",
    "Title": "Title1",
    "User": [
        {
            "Id": "Userid2",
            "Title": "User Title1",
            "Concerts": [
                {
                    "Id": "Concert4",
                    "Title": "Concert title1",
                    "Users": {
                        "Id": "Userid2",
                        "Title": "User Title2 Concert4"
                    }
                },
                {
                    "Id": "Concert1",
                    "Title": "Concert title1",
                    "Users": {
                        "Id": "Userid2",
                        "Title": "User Title2 Concert1"
                    }
                }
            ]
        },
        {
            "Id": "Userid1",
            "Title": "User Title1",
            "Concerts": [
                {
                    "Id": "Concert1",
                    "Title": "Concert title1",
                    "Users": {
                        "Id": "Userid1",
                        "Title": "User Title Concert1"
                    }
                },
                {
                    "Id": "Concert2",
                    "Title": "Concert title1",
                    "Users": {
                        "Id": "Userid1",
                        "Title": "User Title Concert2"
                    }
                },
                {
                    "Id": "Concert3",
                    "Title": "Concert title1",
                    "Users": {
                        "Id": "Userid1",
                        "Title": "User Title Concert3"
                    }
                }
            ]
        }
    ]
}