使用条件json.net反序列化对象

你可以通过 NullValueHandling 标志到 JsonProperty 属性(如果您使用的是newtonsoft)。以下是他们文档中的一个示例:

https://www.newtonsoft.com/json/help/html/JsonPropertyPropertyLevelSetting.htm

编辑 尝试创建以下对象结构:

public class Person
{
    public string Email { get; set; }
    public DateTime CreatedDate { get; set; }
    public List<Role> Roles { get; set; }
}

public class Role
{
    public string name { get; set; }
    public string type { get; set; }

    [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
    public string town { get; set; }
}

然后将json复制到一个文件中,并像这样反序列化

string json = File.ReadAllText("a.json");
Person person = JsonConvert.DeserializeObject<Person>(json);

编辑

好吧,如果你真的不想看到这个属性,你会得到一些难看的代码。这里有一个简单而肮脏的例子。

public class PersonA
{
    public string Email { get; set; }
    public DateTime CreatedDate { get; set; }
    public List<RoleB> Roles { get; set; }       
}

public class RoleB : RoleA
{
    public string town { get; set; }
}

public class PersonB
{
    public string Email { get; set; }
    public DateTime CreatedDate { get; set; }
    public List<RoleA> RolesA { get; set; } = new List<RoleA>();
    public List<RoleB> RolesB { get; set; } = new List<RoleB>();
}

public class RoleA
{
    public string name { get; set; }
    public string type { get; set; }
}

然后做这样的事情:

string json = File.ReadAllText("a.json");
PersonA personA = JsonConvert.DeserializeObject<PersonA>(json);
PersonB personB = new PersonB() { Email = personA.Email, CreatedDate = personA.CreatedDate };

foreach(var role in personA.Roles)
{
    var roleB = role as RoleB;
    if (roleB.town != null)
    {
        personB.RolesB.Add(roleB);
    }
    else
    {
        personB.RolesA.Add(new RoleA() { name = roleB.name, type = roleB.type });
    }
}