在C# MVC中,如果使用entity framework做数据源,在模型对象中存在引用的时候,直接使用 return Json(object)会报循环引用异常。
解决的方案如下:
创建一个继承自JsonResult的类,内容如下
namespace xxx.Controllers
{
/// <summary>
/// 重写的jsonresult,处理ef model专用
/// </summary>
public class JsonNetResult : JsonResult
{
public JsonSerializerSettings Settings { get; private set; }
public JsonNetResult()
{
Settings = new JsonSerializerSettings
{
//这句是解决问题的关键,也就是json.net官方给出的解决配置选项.
ReferenceLoopHandling = ReferenceLoopHandling.Ignore,
DateFormatHandling= DateFormatHandling.MicrosoftDateFormat,
DateFormatString = "yyyy-MM-dd HH:mm:ss",
};
}
public override void ExecuteResult(ControllerContext context)
{
if (context == null)
throw new ArgumentNullException("context");
if (this.JsonRequestBehavior == JsonRequestBehavior.DenyGet && string.Equals(context.HttpContext.Request.HttpMethod, "GET", StringComparison.OrdinalIgnoreCase))
throw new InvalidOperationException("JSON GET is not allowed");
HttpResponseBase response = context.HttpContext.Response;
response.ContentType = string.IsNullOrEmpty(this.ContentType) ? "application/json" : this.ContentType;
if (this.ContentEncoding != null)
response.ContentEncoding = this.ContentEncoding;
if (this.Data == null)
return;
var scriptSerializer = JsonSerializer.Create(this.Settings);
using (var sw = new StringWriter())
{
scriptSerializer.Serialize(sw, this.Data);
response.Write(sw.ToString());
}
}
}
}
然后创建一个继承自Controller的BaseController
写入如下代码
/// <summary>
/// 重写mvc默认jsonresult使其能够兼容ef的model,不会loop
/// </summary>
/// <param name="data"></param>
/// <param name="contentType"></param>
/// <param name="contentEncoding"></param>
/// <param name="behavior"></param>
/// <returns></returns>
protected override JsonResult Json(object data, string contentType, Encoding contentEncoding, JsonRequestBehavior behavior)
{
return new JsonNetResult
{
Data = data,
ContentType = contentType,
ContentEncoding = contentEncoding,
JsonRequestBehavior = behavior
};
}
然后上层控制器,继承自BaseController,正常使用return Json(object) 即可
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