问题
The error I'm getting seems to be coming out of the Structs.tt file. I'm using the Northwind db and only using the Products table (I excluded all other tables). I return Json(Product.All()).
Here's the error:
A circular reference was detected while serializing an object of type 'SubSonic.Schema.DatabaseColumn'.Here's the Stack Trace:
System.InvalidOperationException was unhandled by user code Message="A circular reference was detected while serializing an object of type 'SubSonic.Schema.DatabaseColumn'." Source="System.Web.Extensions" StackTrace: at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeCustomObject(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeCustomObject(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeEnumerable(IEnumerable enumerable, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeCustomObject(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeEnumerable(IEnumerable enumerable, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeCustomObject(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, SerializationFormat serializationFormat) at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj) at System.Web.Mvc.JsonResult.ExecuteResult(ControllerContext context) at System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass11.b__e() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass11.<>c__DisplayClass13.b__10() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList1 filters, ActionResult actionResult) at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) at System.Web.Mvc.Controller.ExecuteCore() at System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) at System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) at System.Web.Mvc.MvcHandler.ProcessRequest(HttpContextBase httpContext) at System.Web.Mvc.MvcHandler.ProcessRequest(HttpContext httpContext) at System.Web.Mvc.MvcHandler.System.Web.IHttpHandler.ProcessRequest(HttpContext httpContext) at System.Web.Mvc.MvcHttpHandler.VerifyAndProcessRequest(IHttpHandler httpHandler, HttpContextBase httpContext) at System.Web.Routing.UrlRoutingHandler.ProcessRequest(HttpContextBase httpContext) at System.Web.Routing.UrlRoutingHandler.ProcessRequest(HttpContext httpContext) at System.Web.Routing.UrlRoutingHandler.System.Web.IHttpHandler.ProcessRequest(HttpContext context) at ExtJSNorthwind._Default.Page_Load(Object sender, EventArgs e) in C:\Applications\Spikes\ExtJSNorthwind\ExtJSNorthwind\Default.aspx.cs:line 18 at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) at System.Web.UI.Control.OnLoad(EventArgs e) at System.Web.UI.Control.LoadRecursive() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) InnerException:
回答1:
Seems we have an issue with Serialization :). Can you please add this as an Issue on our list? I'd really appreciate it.
回答2:
This is fairly easy to fix. You need to just add a ScriptIgnore attribute to a couple of the methods in the ActiveRecord.tt file. Below are the changes that I made.
[ScriptIgnore]
public IList<IColumn> Columns{
get{
return tbl.Columns;
}
}
Note: I also added the attribute to the following method though I don't know if it is needed in your situation
[ScriptIgnore]
public IQueryable<<#=fk.OtherClass #>> <#=propName #>
{
get
{
var repo=<#=Namespace #>.<#=fk.OtherClass#>.GetRepo();
return from items in repo.GetAll()
where items.<#=CleanUp(fk.OtherColumn)#> == _<#=CleanUp(fk.ThisColumn)#>
select items;
}
}
来源：https://stackoverflow.com/questions/1193857/subsonic-3-0-0-2-structs-tt