无法将“System.String”类型的对象转换为“System.Collections.Generic.List”1

Question

我试图将 json 字符串反序列化为一个复杂的对象，但没有成功：

这是我试图反序列化的类：

public class ExcludePublisherRule : BaseAutomaticRule
{

    public int LineIdx { get; set; }

    [Required]
    [Range(30, 1000)]
    public int MininumInstalls { get; set; }

    [Required]
    public int UsingDataFrom { get; set; }

    [Required]
    public List<PostEventModel> PostEventsModels { get; set; }

}

public abstract class BaseAutomaticRule
{
    public int Id { get; set; }

    [Required(ErrorMessage = "*Rule name is required")]
    [StringLength(70)]
    public string Name { get; set; }

    public DateTime LastActivated { get; set; }

    [Required]
    public string CampaignId { get; set; }

    public int StatusId { get; set; }
}


public class PostEventModel
{
    public int Id { get; set; }
    public int PublisherInstalls { get; set; }
}


This is how I try to do it:
//Get type and Object and returns a class object.
    public T ConvertToAutomaticRule<T>(dynamic automaticRuleJSON)
    {
        var json = "";
        try
        {
            var serializer = new JavaScriptSerializer();
            json = serializer.Serialize(automaticRuleJSON);
            return serializer.Deserialize<T>(json);
        }
        catch (Exception ex)
        {
            log.Error($"Ex message: {ex.Message}, json is {json}");
            return default(T);
        }

    }

json：

{"automaticRuleName":"asd","installsNumber":"30","usingDataFrom":"1","ruleStatusId":"1","automaticRuleID":"0","PostEventsModels":"[{\"Id\":\"23\",\"PublisherInstalls\":\"15\"},{\"Id\":\"2\",\"PublisherInstalls\":\"96\"}]","campaignId":"95e62b67-ba16-4f76-97e4-dd96f6e951c7"}

但是我一直收到上面的错误，这种方式有什么问题？

Answer 1

JSON 明确表示它是一个字符串，而不是一个数组；

"PostEventsModels":"[{\"Id\":\"23\",...

应该：

"PostEventsModels":[{"Id":23,...

修复源 JSON

Answer 2

如果您格式化 json（例如在https://jsonformatter.curiousconcept.com/ 上），您可以看到该属性PostEventsModels不是 json 列表，而是它的字符串表示形式。

{  
   "automaticRuleName":"asd",
   "installsNumber":"30",
   "usingDataFrom":"1",
   "ruleStatusId":"1",
   "automaticRuleID":"0",
   "PostEventsModels":"[{\"Id\":\"23\",\"PublisherInstalls\":\"15\"},{\"Id\":\"2\",\"PublisherInstalls\":\"96\"}]",
   "campaignId":"95e62b67-ba16-4f76-97e4-dd96f6e951c7"
}

所以需要更正json生成，或者让propertyPostEventsModels为字符串，稍后再反序列化这个字符串。