Changing maxJsonLength property in web.config has no effec - asp.net

Question

I am using an MS Virtual Earth AJAX control to plot custom boundaries on a map in my ASP.Net 3.5 site. I have a WCF service which I call from ASP.Net to return the points I need to plot. In one instance, I need to plot ~40,000 points.
I get the following error any time the amount of points (rows returned from WCF service) I need to plot are over 25,000.
Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.
I tried modifying the maxJsonLength property in my web.config to 2147483647 but changing this value has no effect. No matter what I set the value to, I always get an error when I try to plot more than 25,000 points. I even tried setting it to "ABC" and my site still worked when my WCF service returned less than 25,000 records.
I verified that I don't have the maxJsonLength property in my machine.config file.
Below is an excerpt from my web.config file:
*<configuration>
<configSections>
<sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
<sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerializationSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="Everywhere"/>
<section name="profileService" type="System.Web.Configuration.ScriptingProfileServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
<section name="authenticationService" type="System.Web.Configuration.ScriptingAuthenticationServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
<section name="roleService" type="System.Web.Configuration.ScriptingRoleServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/></sectionGroup></sectionGroup></sectionGroup></configSections><appSettings/>
<connectionStrings/>
<system.web.extensions>
<scripting>
<webServices>
<jsonSerialization maxJsonLength="2147483647"/>
</webServices>
</scripting>
</system.web.extensions>*
Any idea my changes to the maxJsonLength property aren't being recognized?

Answer 1

You can try to change it from WCF service
var jsonResult = Json(data, JsonRequestBehavior.AllowGet);
jsonResult.MaxJsonLength = int.MaxValue;
return jsonResult;

Answer 2

Additionally, add following key to appSettings:
<appSettings>
<add key="aspnet:MaxJsonDeserializerMembers" value="2147483647" />
...
</appSettings>
At least in Mvc, this setting is enough to solve this problem.