如何在JSON.NET对象中基于条件语句添加Jproperty

Question

我想根据条件语句的结果在JObject中添加JProperty字段，但是我很难格式化代码。

string zip = "00000";
bool isNull = string.IsNullOrEmpty(str);
JObject jsonContent = new JObject(
            new JProperty("email_address", subscriber.Email),
            new JProperty("status", "subscribed"),
            if(!isNull)
            {
                 new JProperty("ZIP", str),
            }
            new JProperty("state": "NY")
        );

问题是如何处理上一行上的逗号，以及如何尤其要格式化JSON对象中的条件语句。

Answer 1

您可以根据条件以后添加该属性，以下呢？

string zip = "00000";
bool isNull = string.IsNullOrEmpty(str);
JObject jsonContent = new JObject(
            new JProperty("email_address", subscriber.Email),
            new JProperty("status", "subscribed"),
            new JProperty("state": "NY")
        );
if(isNull) {
    jsonContent["ZIP"] = str;
}

Answer 2

您可以根据条件实例化JProperty或null，然后在属性周围设置查询以跳过null，如：

var obj =
    new JObject(
        from p in new[]
        {
            new JProperty("email_address", subscriber.Email),
            new JProperty("status", "subscribed"),
            // conditional property:
            zip is not null ? new JProperty("ZIP", zip) : null,
            new JProperty("state", "NY")
        }
        where p is not null // skip null properties
        select p);

当您将复杂的JSON对象设置为单个表达式时，这可能会有所帮助。如果查询部分打扰，则可以将其塞在辅助方法后面：

using static JsonNetHelpers; // import members of this type
var obj =
    JObject( // invokes "JObject" method; not "JObject" constructor (new missing)
        new JProperty("email_address", subscriber.Email),
        new JProperty("status", "subscribed"),
        // conditional property:
        zip is not null ? new JProperty("ZIP", zip) : null,
        new JProperty("state", "NY"));
static class JsonNetHelpers
{
    public static JObject JObject(params JProperty?[] properties) =>
        new JObject(from p in properties where p is not null select p);
}