Tuesday, 10 July 2012

Could not load type 'System.Web.Http.Dependencies.IDependencyScope'

I am working on one Asp.Net WebApi project along with 5 members in my team. We are using
Asp.net MVC4  Beta for the WebApi project. Everything is working for me fine. Suddenly one day I got the latest version of code from TFS and try to run the application. The solution build succeed, but the application throwing the following exception.
Could not load type 'System.Web.Http.Dependencies.IDependencyScope' from assembly 'System.Web.Http, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'
The same application is running in my other teammates. I researched around one day, but did not found any solution that why this dll is not loading run time even though the dll is present in the bin folder.  One of my team mate told that Asp.Net MVC4 is updated from beta to release version. I updated that in my system then the application is working fine. There was mismatch in the team communicatin about this updatation I lost my one day. If any one get this exception try to update the WebApi to release candidate.

Tuesday, 5 June 2012

Date Comparision in Entity Framework

When we are writing linq expression in Entity framework as follows
context.GetQuery<TaxLocExtract>().Where(
tle => tle.EffectiveDate.Date == effectiveDate.Date).ToList();
then we will get the following exception
The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.
the solution to resolve is System.Data.Objects.EntityFunctions.TruncateTime() is used. the sample query as follows.
context.GetQuery<TaxLocExtract>().Where(
tle => System.Data.Objects.EntityFunctions.TruncateTime(tle.EffectiveDate) == System.Data.Objects.EntityFunctions.TruncateTime(effectiveDate)).ToList();
I hope this solution helps.

Friday, 18 May 2012

structuremap 2.6 IncludeConfigurationFromConfigFile=true not working

When we are using structuremap 2.6.x  and adding structuremap configuration in the app.config/web.config. To  include configuration every one set the property IncludeConfigurationFromConfigFile=true. It is not working and seems to be not implemented. But when we are refering same app.config with AddConfigurationFromXmlFile(configfilepath) then it is working fine. when we are using app.config the file name of configuration is changed after the solution build. To include that configuration file find the solution below.
To get the name and path of configuration file as follows
var configName = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile; 
The example method and usage as follows:

 private static IContainer InitiazlizeFromAppConfigOrWebConfig()
 {
   var configName = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile; 
    return new Container(x =>
    {
     x.AddConfigurationFromXmlFile(configName);
      //x.IncludeConfigurationFromConfigFile = true; //seems not imeplemented
    });
}

Wednesday, 16 May 2012

ObjectFactory Vs Container StructureMap

ObjectFactory is a static gateway for an instance of container. If you only ever want one instance of a container, and want a simple static way to get at it, use ObjectFactory. You must Initialize the ObjectFactory, and then retrieve your instances via ObjectFactory.

 Alternatively, if you want to manage the lifetime of the container yourself, you can create an instance of Container, passing an initialization expression to the constructor. You then retrieve instances from the variable you declared to store the Container.

Thursday, 26 April 2012

[Fixed]How to overcome the linq contains limitation.Too many parameters were provided in this RPC request. the maximum is 2100

When we want to filter the data from the Linq to Sql query with the collection every one is trying to use the Contains() operator as follows. Linq to Sql will try to generate a sql query to represent the whole expression. This means that it will try to pass in the collection as parameters to a sql query. If there are too many parameters the query will hit the parameter limit (2100) and it cannot be executed. If there are not that many parameters, then you can use a contains expression which will be converted to an "IN" expression in sql. Sample code as follows
List<int> contactIds=Contact.GetContactIds()
//count of contactIds is morethan 2100
var contacts = Context.Contacts.Where(c => contactIds.Contains(c.ContactId)).ToList();
If the parameter limit exeeds then the following exception throws.
The incoming tabular data stream (TDS) remote procedure call (RPC) protocol stream is incorrect. Too many parameters were provided in this RPC request. The maximum is 2100.
To avoid this many developers will try to join the in memory collection with database table as follows. 
List<int> contactIds=Contact.GetContactIds()
//count of contactIds is morethan 2100
var contacts = Context.Contacts.Join(contactIds, c => c.ContactId, ci => ci, (c, ci) => c).ToList();
When developer trying this the following exception throws.
Local sequence cannot be used in LINQ to SQL implementations of query operators except the Contains operator.
This means that the linq to sql generates sql query and executes on the database server. Our in memory collection will not support to execute on the database server. so will get the above exception.
The easiest resolution is to convert the LINQ to SQL table into an IEnumerable list, which can be done as follows.
List<int> contactIds=Contact.GetContactIds()
//count of contactIds is morethan 2100
var contacts = Context.Contacts.AsEnumerable().Join(contactIds, c => c.ContactId, ci => ci, (c, ci) => c).ToList();
I hope this solution helps you.

Wednesday, 25 April 2012

How to render partial view on each telerik Panel bar

The solution to render the partilal view on telerik panel bar or each panel bar contains one from is as follows. Here partial view contains form.
  @(
     Html.Telerik().PanelBar().Name("PanelBar").HtmlAttributes(new { style = "width: 300px;" }).BindTo(Model, mappings =>
      {
       mappings.For(binding => binding.ItemDataBound((item, manager) =>
       { 
         item.Text = manager.Name;
          item.Html = Html.Partial("Manager_Partial",manager).ToHtmlString();
          }));
         })
   )

How to read the conig file of class library in C Sharp

Every body knows that we can define the appsettings in the app.config file of class library. When we are refering the existing class library to the other new class library that only takes dll but not the configuration file of existing class library. To read values from the configuration file one option is to define same appsettings in the new class library. the other solution is as follows.

Solution:

  1. Refer the class library to the other new class library.
  2. Copy the .dll.config file from bin/debug folder of the existing class library and add to the new class library.
  3. Use the following code to get the values from the .dll.config file.
/// Load the .config file for the current DLL
System.Reflection.Assembly assembly = System.Reflection.Assembly.GetExecutingAssembly();

Configuration dllConfig = ConfigurationManager.OpenExeConfiguration(assembly.Location);

KeyValueConfigurationCollection settings = dllConfig.AppSettings.Settings;
//read the value as follows
string value=settings[key].value;