我使用的是Json。将类序列化为JSON。
我的课程是这样的:
class Test1
{
[JsonProperty("id")]
public string ID { get; set; }
[JsonProperty("label")]
public string Label { get; set; }
[JsonProperty("url")]
public string URL { get; set; }
[JsonProperty("item")]
public List<Test2> Test2List { get; set; }
}
我想仅当Test2List为空时才向Test2List属性添加JsonIgnore()属性。如果它不是空的，那么我想包括它在我的json。
当前回答
这里有一个类似的选项，但提供了另一种选择:
public class DefaultJsonSerializer : JsonSerializerSettings
{
public DefaultJsonSerializer()
{
NullValueHandling = NullValueHandling.Ignore;
}
}
然后，我这样使用它:
JsonConvert.SerializeObject(postObj, new DefaultJsonSerializer());
不同之处在于:
Reduces repeated code by instantiating and configuring JsonSerializerSettings each place it's used. Saves time in configuring every property of every object to be serialized. Still gives other developers flexibility in serialization options, rather than having the property explicitly specified on a reusable object. My use-case is that the code is a 3rd party library and I don't want to force serialization options on developers who would want to reuse my classes. Potential drawbacks are that it's another object that other developers would need to know about, or if your application is small and this approach wouldn't matter for a single serialization.
其他回答
var settings = new JsonSerializerSettings();
settings.ContractResolver = new CamelCasePropertyNamesContractResolver();
settings.NullValueHandling = NullValueHandling.Ignore;
//you can add multiple settings and then use it
var bodyAsJson = JsonConvert.SerializeObject(body, Formatting.Indented, settings);
.Net 6 - 在Program.cs中添加代码。这将忽略类或记录属性，如果它是空的。
using System.Text.Json.Serialization;
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddControllers()
.AddJsonOptions(opts =>
{
var enumConverter = new JsonStringEnumConverter();
opts.JsonSerializerOptions.Converters.Add(enumConverter);
opts.JsonSerializerOptions.DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingDefault | JsonIgnoreCondition.WhenWritingNull;
});
这里有一个类似的选项，但提供了另一种选择:
public class DefaultJsonSerializer : JsonSerializerSettings
{
public DefaultJsonSerializer()
{
NullValueHandling = NullValueHandling.Ignore;
}
}
然后，我这样使用它:
JsonConvert.SerializeObject(postObj, new DefaultJsonSerializer());
不同之处在于:
Reduces repeated code by instantiating and configuring JsonSerializerSettings each place it's used. Saves time in configuring every property of every object to be serialized. Still gives other developers flexibility in serialization options, rather than having the property explicitly specified on a reusable object. My use-case is that the code is a 3rd party library and I don't want to force serialization options on developers who would want to reuse my classes. Potential drawbacks are that it's another object that other developers would need to know about, or if your application is small and this approach wouldn't matter for a single serialization.
在。net Core中，这就容易多了。在你的startup.cs中添加json选项，你可以在那里配置设置。
public void ConfigureServices(IServiceCollection services)
....
services.AddMvc().AddJsonOptions(options =>
{
options.SerializerSettings.NullValueHandling = NullValueHandling.Ignore;
});
您可以这样做来忽略正在序列化的对象中的所有空值，因此任何空属性都不会出现在JSON中
JsonSerializerSettings settings = new JsonSerializerSettings();
settings.NullValueHandling = NullValueHandling.Ignore;
var myJson = JsonConvert.SerializeObject(myObject, settings);
