C#中[JsonIgnore]意义

字面意义是忽略序列化，就是当字段在序列化时，被[JsonIgnore]标记了的字段将被忽略序列化

 

序列化输出中使用Id和Name属性,但我绝对不会对AlternateName和Color感兴趣.我用[JsonIgnore]标记了那些.我希望描述出现,但有时这可能会变得很长,所以我使用自定义JsonConverter来限制它的长度.我还想使用较短的属性名称来描述,所以我用[JsonProperty(“Desc”)]标记了它.

class Foo { public int Id { get; set; } public string Name { get; set; } [JsonIgnore] public string AlternateName { get; set; } [JsonProperty("Desc")]//替换序列化名 [JsonConverter(typeof(StringTruncatingConverter))] public string Description { get; set; } [JsonIgnore] public string Color { get; set; } }

当我序列化上面的一个实例时……

Foo foo = new Foo
{
    Id = 1, Name = "Thing 1", AlternateName = "The First Thing", Description = "This is some lengthy text describing Thing 1 which you'll no doubt find very interesting and useful.", Color = "Yellow" }; string json = JsonConvert.SerializeObject(foo, Formatting.Indented);

…我得到这个输出：

{
  "Id": 1, "Name": "Thing 1", "Desc": "This is some lengthy text describing Thing 1 " }

我有时想获得完整的JSON输出,忽略我的自定义.我可以使用自定义ContractResolver以编程方式“取消应用”类中的属性.这是解析器的代码：

class IgnoreJsonAttributesResolver : DefaultContractResolver { protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization) { IList<JsonProperty> props = base.CreateProperties(type, memberSerialization); foreach (var prop in props) { prop.Ignored = false; // Ignore [JsonIgnore] prop.Converter = null; // Ignore [JsonConverter] prop.PropertyName = prop.UnderlyingName; // restore original property name } return props; } }

要使用解析器,我将它添加到JsonSerializerSettings并将设置传递给序列化器,如下所示：

 

JsonSerializerSettings settings = new JsonSerializerSettings();
settings.ContractResolver = new IgnoreJsonAttributesResolver(); settings.Formatting = Formatting.Indented; string json = JsonConvert.SerializeObject(foo, settings);

输出现在包括被忽略的属性,并且描述不再被截断：

 

{
  "Id": 1, "Name": "Thing 1", "AlternateName": "The First Thing", "Description": "This is some lengthy text describing Thing 1 which you'll no doubt find very interesting and useful.", "Color": "Yellow" }


原文：http://www.voidcn.com/article/p-uvkjwmre-bub.html