Call Stored Procedure from Entity Framework

Microsoft have introduced entity framework to connect to the database. When you work with the database, you have to call your stored procedure. This blog explain you how to execute your stored procedure from Entity Framework.

Assume that your stored procedure insert/update/delete record into database. It returns nothing just do as per the parameter value.

Follow the below steps:
1. Open Entity Framework Model page in Visual Studio IDE
2. Right click on blank area and choose “Add” -> “Function Import” option
3. In Add Function Import dialog, select your stored procedure, give function name and choose return type
4. Click on Ok button to add the function in Entity Framework
5. In your page, Create instance of entities class and call your function with proper parameter value

If your stored procedure is return multiple record then you have to create one custom entity, which have the same schema as your stored procedure return the data. To create the custom entity, right click on Entity Framework Model page and choose “Add” -> “Entity…” It will open “Add Entity” dialog box where you have to give Entity Information.

You can add/edit/delete properties into custom activity. To add, Select “Scalar Properties” section under custom activity, right click and choose “Add” -> “Scalar Property”.

Just create custom entity. After creating custom entity, Add Function Import to your entity framework model.

Follow the below steps:
1. Open Entity Framework Model page in Visual Studio IDE
2. Right click on blank area and choose “Add” -> “Function Import” option
3. In Add Function Import dialog, select your stored procedure, give function name and choose return type as Entities and select your custom entity from dropdown list.
4. Click on Ok button to add the function in Entity Framework
5. In your page, Create instance of entities class and call your function with proper parameter value


TestDBEntities1 testdb = new TestDBEntities1();
var p = from d in testdb.GetOrderInfo() select d;

Entity Framework Stored Procedure mapping

Introduction

Now days, Microsoft have changed lots of thing in accessing database from .Net application. Microsoft has introduced Entity Framework to access database from the application. Entity framework is just a small wizard which helps to create classes to access the database. To know basic of Entity Framework please click on here.

In Part 1, I explained you how to create entity framework class in your project and how to insert, update or delete the record. Now in part 2, I explain you how to map your stored procedure with insert, update and delete functionality.

If you will not map your stored procedure then Entity Framework will create concrete SQL statement for insert, update and delete. If you will map your stored procedure then Entity Framework will execute your stored procedure with parameter value.

Let take an example of contact table which I explained schema in part 1.

After creating entity framework file (.edmx), Select “Contact” entity and open “Mapping Details” window. In Mapping Details window, click on “Map Entity to Function” button on left side. Refer below screen shot:




In Insert/Update/Delete function, Select your stored procedure and map your parameter value. Refer image below:



Now you have to just add/update/remove data using Entity Framework and It will execute your mapped stored procedure.

Following code is used to add new record into Contact table. When user will execute the code below, Entity Framework will execute “SPE_ContactInsert” stored procedure to insert contact information.

TestEntityEntities testEntityEntities = new TestEntityEntities();
Contact contact = new Contact();
contact.FirstName = "test1";
contact.LastName = "test2";
contact.Title = "Mr.";
testEntityEntities.AddToContact(contact);
testEntityEntities.SaveChanges();

As the same way you can update or delete the record. For more information please refer Entity Framework part 1 here.

Register .net assembly as COM

Introduction
We have used VB6.0 DLL or OCX component in our .Net application. But sometime we need to use our .Net DLL into VB6.

In the following scenario you need to use .Net DLL into VB6.

• Any third party module is available in .Net and you need to integrate it with your VB6.0 application


• Your some modules are already developed into .Net and you have to integrate it with VB6.0 application

This blow will explain you how to create COM compatible .Net assembly step by step.

First we need to create one class library project. Open Visual Studio and create new Class Library project. Give “DemoClassLibrary1” name to your class library.

Create new class which needs to be expose as a COM object. Just add new class into your class library project. Give “DemoClass1” to your class name.


Public Class DemoClass1

Public Function GetWelcomeString(ByVal name As String) As String
GetWelcomeString = "Welcome " + name
End Function

End Class

Now to create it COM compatible, you have to add ComClass attribute on your class definition. So updated code will look like below:



Public Class DemoClass1

Public Function GetWelcomeString(ByVal name As String) As String
GetWelcomeString = "Welcome " + name
End Function

End Class

I have created one method which will be exposed as a COM method.

You also need to set your project as a Com compatible. To configure it, open project property. Right click on project in solution explorer and select properties option. In compile tab, select checkbox “Register for COM Interop”.

Now when you will build your project, project will create DLL as well as TLB file. This TLB file needs to use your .Net DLL into VB6.

Let’s use this DLL into VB6. Open your VB6 project and open reference dialog to add your .Net class reference. You will get option for “DemoApplication1”, select the option and click on ok.

Now you can create object of “DemoClass1” and use your function “GetWelcomeString”.

If you want to use this component on another machine then you have to copy the DLL file on that machine and register your DLL file to the registry so your VB6 application can find your component.

To register the component, Open Visual Studio 2008 command prompt and execute following command.


Regasm <<DLL file full path>> /tlb:<<tlbfilename>> /codebase

Regasm command generate TLB file and also register it with the system. Codebase option also set the code base with the registry.

SQL Server 2005 Integration Service Basic

Introduction

SQL Server Integration service is mainly used to transfer data from one database to another in different format. Also it is used to manipulate data before storing on destination.

SSIS (SQL server Integration Service) is specially designed for ETL process. ETL stands for Extract, Transform and Loading.

SSIS create package which you can execute from the SQL server management studio, stored procedure or SQL server job which extract data from one database, manipulate it and store it in another database. Here both databases may be different.

You can use any of the following database connection with SSIS package:

• SQL Server


• Flat File


• OLEDB


• ADO.Net


• Analysis Service

Prerequisite:
We need SQL Server Business intelligence development studio (BIDS) tool to develop SSIS package. BIDS tools come with Microsoft SQL Server Installation. Installing Microsoft SQL Server, Please check “Analysis Service” and “Integration Service” option.

In this blog, I will explain you how to create simple SSIS package and execute it from the SQL Server Business Intelligence development studio.

Open SQL Server Business Intelligence Development studio. Follow the following steps to create new SSIS package.

• Create new project from “File” menu -> “New Project”.


• Select “Business Intelligence Projects” from Project types in New Project dialog box


• On right side, you can see different Template available for “Business Intelligence Projects” type. Select “Integration Service Project” template from the available template.


• Give appropriate project name. Here I am giving “DemoIntegrationProject”


• Select Location where you want to save the file. And also give solution name. I am giving “DemoIntegrationSolution”.


• Click on Ok button to create new SSIS project.

The New project dialog box will display as below:



BIDS creates new project and open that project. You can see the available files and objects in Solution explorer. Open solution explorer if it is not opened.

You get four folder in solution explorer included into the project.

• Data Sources: This folder contains information about all data source used into the project.


• Data Source Views: This folder contains the views (UI) of used schema from the data sources.


• SSIS Packages: This folder contains all SSIS packages.


• Miscellaneous

Projects template add one blank SSIS package “Package.dtsx” into the project. We will first understand “Data sources” and “Data Source Views” to understand SSIS package.

Data Sources:
Select “Data Sources” folder in solution explorer. Right click on that. You will get “New Data Source…” option to create new data source. Just click on “New Data Source…” option.

“New Data Source…” option open wizard to create and add new data source into project. Follow the below steps to create new data source:

• On welcome screen, click on Next button


• On “Select how to define the connection” screen, you can see existing data connections (if you used SSIS before and added into any project). Refer screen below
  
  
  


• Select data connection if exist in the list. If your required connection is not available then you can create new connection using “New…” button.


• If connection is not already exist then click on “New…” button. It will open connection manager dialog. On Connection Manager dialog, select appropriate provider. Provide information necessary to create new data connection. Test your input information using “Test Connection” button. If your connection test successfully then Click on Ok to create new connection. Refer screen below
  
  
  


• You will get your connection on “Select how to define the connection” dialog. Select your connection and click on Finish button


• Give your connection name and click on Finish button.

Now you will get new data source file under “Data Sources” folder in solution explorer.

Data Source Views:
You have to create data source views before using data source into SSIS package. To create new “data source view”, select “Data Source Views” folder in solution explorer and right click on it. Select “New Data Source View…” option.

New Data Source View dialog open. Follow the below steps create new data source view:

• On welcome screen, click on Next button


• On “Select a data source” screen, select the data source which you have created. You can create new data source using “New Data Source…” button.


• After selecting data source, click on next button


• On “Select Tables and Views” dialog box, Add required tables to Included objects list box. You can add related objects using “Add Related Tables” button. You can also filter available objects using Filter text box. Add all required tables and views and click on Next button. Refer screen below:
  
  
  


• On “Completing the wizard” screen, give “Data source view” name (Here I gave it to “Test DB”) and click on Finish button.


• It will add new data source view file in the project.

Data Source View editor have three panes: Diagram Organizer, Tables, and Diagram.

Diagram Organizer: Diagram organizer pane allows you to create new Diagram and organize table into sub set. If you have 500 tables/views on Data Source view, then it will be difficult to refer any particular table or related tables. So you can make different Diagram using Diagram organizer pane. Just right click on “” and select “New Diagram” option. It will open new diagram where you can add only your required tables from “Tables” pane.

Tables: Tables pane contains all tables and views selected while creating data source view. After creating data source view, you can add/remove any objects. To add new table/view, just click on “Add/Remove objects” button in tool bar. It is displayed just above Diagram organizer pane.

Diagram: Diagram pane displays all tables and views schema and relation between them.

You can rename table/view and your field name. Sometime your database table/view name is not user friendly like the above diagram “tblProducts” table name is not user friendly. To rename table/view/field name, just select it in Diagram pane and open properties windows. In properties window, change FriendlyName property to give some meaningful name. I have change table names and the updated diagram is displayed as below:



SSIS Package:
You can create new SSIS package using right clicking on “SSIS Packages” folder in Solution explorer and select “New SSIS Package” option.

After package file is added into the solution you can rename to give proper name. When you will rename the package, it gives message to open the SSIS package click on yes to open the package.

SSIS package editor have four tabs:

• Control Flow


• Data Flow


• Event Handlers


• Package Explorer

Control Flow: You can add any number of control flows on your SSIS package. Control flow is just like a one task which you want to accomplish using SSIS package. BIDS tool have many integrated tools available to work with your project. Following are the most usable control flow tasks:

• Bulk Insert Task


• Data Flow Task


• Data Mining Query Task


• Execute Package Task


• Execute Process Task


• Execute SQL Task


• For loop container


• Foreach loop container


• FTP Task


• Script Task


• Send Mail Task


• Web service Task


• Xml Task

There are many other tasks available to create SSIS package as per your requirement.

Data Flow: Data flow is detailed definition of “Data Flow Task” which is available to add in Control Flow. You have seen “Data Flow Task” item available in above list to add into Control Flow tab. When you will add Data Flow Task, you can see those data flow task name in “data flow task” combo box in Data Flow tab.





Now we will create one sample SSIS package, deploy it and execute it from Business Intelligence development studio.

• Open your SSIS Package and open “Control Flow” tab.


• In Control Flow tab, Right click in “Connection Managers” pane and select “New Connection from Data Source…”


• It will open “Select Data Source” dialog box where you can see the Data sources added in your project.


• Select the proper data source and click Ok button. It will add that data connection into your SSIS package. Refer screen below:

• After successfully adding connection manager, Add Data Flow task control on your control flow.


• Right click on Data Flow Task in Control Flow tab and select Property. Change name property from “Data Flow Task” to “Export Customer Data”


• Go to Data Flow Tab


• Add “OLE DB Source” Task on “Data Flow” tab


• Double click on “OLE DB Source” task to open OLE DB Source Editor


• In editor, Select Connection Manager, Data Access mode and other required items. For demo purpose select “Test DB” as a connection manager, “Table or View” as a data access mode and select tblCustomers as a table.


• Click on Ok button.


• Now drag and drop “Flat File Destination” control on Data Flow tab


• Select “Ole Db Data Source” control, you can see green and red arrow. Just hold green arrow and put it on “Flat file destination” control.
  
  Green arrow – Green arrow is used to follow the process if preceding task is completed successfully. In our case, if we get customer data successfully then only go to flat file destination to export it.
  
  Red arrow – Red arrow is used to follow the process if preceding task is completed with error. You can use “Send Mail” task to send the error information or save those error in another destination.

• Double click on “Flat File Destination” control to open control editor


• Create new connection for Flat file. Click on New button to create new connection.


• Select “Delimited” option to generate Flat file connection manager.


• Give proper name and browse the file path


• Click on Ok to add connection manager to your project.


• Click on ok in “Flat File destination editor”

Now you simple package is ready. This package will read customer data from the database and put it in Flat file (Comma separated). You can also use another controls to process the data. You can also filter the data in OLEDB Source control.

When you will execute SSIS package, Business Intelligence development studio will execute your task and transfer customer data from database to your flat file.

Still you have not deployed SSIS package. You can deploy it in SQL server. Follow the below steps:

• Open SQL Server and login on server using Integration service. (In login dialog box, you have to select server type as a Integration service)


• After successfully connecting, expand “Stored Packages” in object explorer.


• Expand “File System”.


• Right click on “File System” and choose “Import Package”


• In Import package dialog, Select “File System” as a Package location


• Select the Package path. Browse to the path where we have created the above SSIS package project and select DTSX file.


• Give the package name and click on ok button to create the package.

You can see your SSIS package under “File System” node in object explorer of SQL server management studio.

You can execute SSIS package from SQL server management studio. Right click on “OrderSSIS” package and choose “Run Package” option. It will open “Execute Package Utility” dialog. Click on Execute button to run the package.

Implementing Singleton Design Pattern in C# application

Introduction

Sometime we need to create only one object of any class in our application then we need to implement Singleton design pattern to achieve this.

For an example, you have logging functionality which takes value as a parameter and store information in external device (like database or xml file or flat file). This logging class doesn’t have any state value. You can design that class using singleton design pattern.

Problem and solution

First problem is that you need to be sure that your class must be initializing once and the reference is available at anytime so your application can use that reference to use singleton class method.

You can solve the above problem using private constructor. When you define private constructor then nobody can initialize object of that class. (Make sure that singleton class doesn’t have any public constructor).

public class SingletonTest
{

private SingletonTest()
{

}

}


Second problem, if you create private constructor then how can we initialize the class first time when we need it?

We can create and initialize object of singleton class (which have only private constructor) within that class. To achieve this we need to implement one public static method which will return object of Singleton class.

public class SingletonTest
{

private static SingletonTest singletonTest = null;

private SingletonTest()
{

}

public static SingletonTest RetrieveObject()
{
if (singletonTest == null)
singletonTest = new SingletonTest();
return singletonTest;
}

}

Now, we can create and initialize object of our singleton class using below code:


SingletonTest singletonTest = SingletonTest.RetrieveObject();

When user will call this method first time, this method will create new object of SingletonTest class and assign it to private static variable and return that variable.

When user will call the same method again, this method will check that the private static variable is initialized. If private static variable is initialized then it will return it. In our case it initialized already when user called this first time.

So it confirms that our SingletonTest class has only one reference during whole application life cycle.

.Net Remoting

Introduction

Sometime we need to call method on remote machine or on the same machine but in different Application Domain. In this scenario, we need to implement Remoting.

We can also use the following options in behalf of Remoting:

• Web service


• MSMQ


• WSE

Remoting is faster than the above things. MSMQ is depended on Microsoft Message Queue. Web service and WSE is slower than .Net Remoting. But Remoting have also some constraint:

• You can use Remoting only when both side application is develop using .Net Framework


• Remoting uses binary serialization. Microsoft has changed their binary serialization in 2003 and 2005. So your both application must be developed using same version of .Net Framework.

Example
Let’s take an example.

To implement Remoting service in your application, you have one common contract for both client and server application. So first we create one class which will be shared on both client and server application.

Open Visual Studio and create one class library. Create one class. For demo purpose I have created one class “CommonClass”.


public class CommonClass : MarshalByRefObject
{

public string FirstName;

public string LastName;

public string GetWelcomeString()
{
Console.WriteLine("Welcome " + FirstName + " " + LastName);
return "Welcome " + FirstName + " " + LastName;
}

}


Please note that, this class must be derived from MarshalByRefObject class. If you will forget to derive your class from MarshalByRefObject class then you will get runtime error “Trying to create a proxy to an unbound type.”


In the above class, I just declared two public variables, FirstName and LastName and add one public method “GetWelcomeString” which return welcome string with first name and last name.

In GetWelcomeString function, we have writes welcome string on console and also return the same string. This method will execute on server side so it will display text on server side and return value to client side.

Now let’s implement server application. Open visual studio and create one console application.

Add following reference in server application project:

• CommonClass library project


• System.Runtime.Remoting

Add the following code into Program.cs file in main method:


static void Main(string[] args)
{
TcpChannel tcpChannel = new TcpChannel(8084);
ChannelServices.RegisterChannel(tcpChannel);
RemotingConfiguration.RegisterWellKnownServiceType(typeof(ClassLibrary1.CommonClass), "testRemoting", WellKnownObjectMode.Singleton);
Console.WriteLine("Server is ready");
Console.ReadLine();
}


In the above code, first we create TcpChannel class object which will be registered with appropriate port number. Please don’t use the currently used port. If you will use the port number which is already used with another application then you will get runtime error.

After registering TcpChannel, We need to just register our class using RemotingConfiguration. First parameter is which type you want to register; give our class type. Second parameter is URI which is used to communicate with server from client application. And last parameter is WellKnownObjectMode.

WellKnownObjectMode is ENUM and contains two values:

• Singleton – which create only one object of our common class and serve all the request using that object only


• SingleCall – which create object every time when user will send a request to server

Now let’s create client application. Open Visual Studio and create new console application.

Add following reference in server application project:

• CommonClass library project


• System.Runtime.Remoting

Add the following code into Program.cs file in main method:


static void Main(string[] args)
{
CommonClass c = (CommonClass)Activator.GetObject(typeof(CommonClass), "tcp://localhost:8084/testRemoting");
Console.WriteLine("Client is ready");
c.FirstName = "Hardik";
c.LastName = "Patel";
Console.WriteLine("Return string: " + c.GetWelcomeString());
Console.ReadLine();
}


First we create object of our CommonClass but we use Activator.GetObject method to get object from the server.

This method has two parameters, first is type of object which you need to get, pass our CommonClass class type.

Second parameter is URL from which we need to get object.

The URL is: tcp://localhost:8084/testRemoting

We used TCP as a channel service so we need to use TCP protocol.
Server is running on the same machine so I have used “localhost”. If you server application is running on different machine then please use that machine name/IP address instead of localhost.
testRemoting is a URI which is defined in server application when we register our class using RemotingConfiguration (Second parameter).

Now execute server application first. After getting “server is ready” message in server application console, execute client application. Server application will display “Welcome Hardik Patel” message and return the same message to client application. Client application also displays the message “Return string: Welcome Hardik Patel”. Please refer screen below:

Workflow Custom Activity – Part 2

Introduction

Windows Workflow foundation gives many activities to use in workflow like code, delay, IfElse, Listen, Parallel etc. But in some scenario, those activities will not work as per our requirement. So we need to implement custom activity which will work as per our requirement.

To create a custom activity, Please visit http://dotnet-codeguru.blogspot.com/2010/02/windows-workflow-foundation-custom.html

In some scenario, you have to create some dynamic property in custom activity. For an example you are creating custom activity for Order Search. In this activity, User can search order by order id or customer id. So you want to give filter where user can select either “Order ID” or “Customer ID”. If user will select Order ID then new property Order Number will display in property window. And if user will select Customer ID then new property Customer Number will display in property window.

It is similar to IfElse Branch condition property. You get two options “Code Condition” and “Declarative Rule Condition”. As per your selection, you will get sub properties.



Let’s implement same thing in custom activity:

To support sub property for Order Search type we need to implement two classes “OrderSearchByOrderID” and “OrderSearchByCustomerID” which are derived from “ActvityCondition” class.

In the above classes, we need to override “Evaluate” method. In this simple scenario, we always return true from the above classes.

In OrderSearchByOrderID class, we need to add one property for OrderID which will display when user select “OrderSearchByOrderID” option from the selection box. The code for the OrderSearchByOrderID class is look like below:


public class OrderSearchByOrderID : ActivityCondition
{
public override bool Evaluate(Activity activity, IServiceProvider provider)
{
return true;
}

private string orderID;

[Browsable(true)]
public string OrderID
{
get
{
return orderID;
}
set
{
orderID = value;
}
}

}


Code for OrderSearchByCustomerID is similar and looks like below:


public class OrderSearchByCustomerID : ActivityCondition
{
public override bool Evaluate(Activity activity, IServiceProvider provider)
{
return true;
}

private string orderID;

[Browsable(true)]
public string OrderID
{
get
{
return orderID;
}
set
{
orderID = value;
}
}
}


We need to develop “TypeConvertor” which helps to display the option in dropdown box in property window.


public class CustomOrderSearchTypeConverter : TypeConverter
{

private Hashtable _conditionDecls = new Hashtable();

public CustomOrderSearchTypeConverter()
{
try
{
AddTypeToHashTable(typeof(OrderSearchByCustomerID));
AddTypeToHashTable(typeof(OrderSearchByOrderID));
}
catch (Exception ex)
{
throw;
}
}

private void AddTypeToHashTable(Type typeToAdd)
{
string key = typeToAdd.FullName;
object[] attributes = typeToAdd.GetCustomAttributes(typeof(DisplayNameAttribute), false);
if (attributes != null && attributes.Length > 0 && attributes[0] is DisplayNameAttribute)
key = ((DisplayNameAttribute)attributes[0]).DisplayName;
this._conditionDecls.Add(key, typeToAdd);
}

public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
try
{
if (sourceType == typeof(string))
{
return true;
}
return base.CanConvertFrom(context, sourceType);
}
catch (Exception ex)
{

throw;
}
}

public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
try
{
string strVal = value as string;
if (strVal != null)
{
if (strVal.Length == 0 || strVal == "")
return null;
else
return Activator.CreateInstance(this._conditionDecls[value] as Type);
}
return base.ConvertFrom(context, culture, value);
}
catch (Exception ex)
{

throw;
}
}

public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
try
{
if (destinationType == typeof(string))
{
return true;
}
else
{
return base.CanConvertTo(context, destinationType);
}
}
catch (Exception ex)
{

throw;
}
}

public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
try
{
if (value == null)
return "";
object convertedValue = null;
if (destinationType == typeof(string) && value is ActivityCondition)
{
foreach (DictionaryEntry conditionTypeEntry in this._conditionDecls)
{
if (value.GetType() == conditionTypeEntry.Value)
{
convertedValue = conditionTypeEntry.Key;
break;
}
}
}
if (convertedValue == null)
convertedValue = base.ConvertTo(context, culture, value, destinationType);
return convertedValue;
}
catch (Exception ex)
{

throw;
}
}

public override StandardValuesCollection GetStandardValues(ITypeDescriptorContext context)
{
try
{
ArrayList conditionDeclList = new ArrayList();
conditionDeclList.Add(null);
foreach (object key in this._conditionDecls.Keys)
{
Type declType = this._conditionDecls[key] as Type;
conditionDeclList.Add(Activator.CreateInstance(declType));
}
return new StandardValuesCollection((ActivityCondition[])conditionDeclList.ToArray(typeof(ActivityCondition)));
}
catch (Exception ex)
{

throw;
}
}

public override bool GetStandardValuesSupported(ITypeDescriptorContext context)
{
try
{
// Always return true.
return true;
}
catch (Exception ex)
{

throw;
}
}

public override bool GetStandardValuesExclusive(ITypeDescriptorContext context)
{
try
{
// Always return true.
return true;
}
catch (Exception ex)
{

throw;
}
}

public override PropertyDescriptorCollection GetProperties(ITypeDescriptorContext context, object value, Attribute[] attributes)
{
try
{
PropertyDescriptorCollection props = new PropertyDescriptorCollection(new PropertyDescriptor[] { });
TypeConverter typeConverter = TypeDescriptor.GetConverter(value.GetType());
if (typeConverter != null && typeConverter.GetType() != GetType() && typeConverter.GetPropertiesSupported())
{
return typeConverter.GetProperties(context, value, attributes);
}
return props;
}
catch (Exception ex)
{

throw;
}
}

public override bool GetPropertiesSupported(ITypeDescriptorContext context)
{
try
{
// Always return true.
return true;
}
catch (Exception ex)
{

throw;
}
}

}


Now we need to use these classes in our custom activity. Just create a new class “OrderSearchActivity” and derive it from “Activity” class.

To give support, we need to implement one dependency property which is ActivityCondition type. Here we declared “OrderSearchTypeProperty” dependency property.

And also implement property for the same “OrderSearchType”.


public static DependencyProperty OrderSearchTypeProperty = DependencyProperty.Register("OrderSearchType", typeof(ActivityCondition), typeof(OrderSearchActivity));

[Description("Order Search Type")]
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
[TypeConverter(typeof(CustomOrderSearchTypeConverter))]
public ActivityCondition OrderSearchType
{
get
{
return ((ActivityCondition)(base.GetValue(OrderSearchTypeProperty)));
}
set
{
base.SetValue(OrderSearchTypeProperty, value);
}
}


Now when you will use this OrderSearchActivity in your workflow then you will see option for OrderSearchType.




If you select “OrderSearchByCustomerID” then you will see “+” sign in front of “OrderSearchType” property which indicate that you have some sub properties. When you click on “+” sign you will get “Customer ID” as a sub property.





Now let’s see how we can use the above property in your custom activity. For this I have override Execute method in OrderSearchActivity.


protected override ActivityExecutionStatus Execute(ActivityExecutionContext executionContext)
{

if (OrderSearchType.GetType() == typeof(OrderSearchByCustomerID))
{
OrderSearchByCustomerID orderSearchByCustomerID = (OrderSearchByCustomerID)OrderSearchType;
string CustomerID = orderSearchByCustomerID.CustomerID;
// User CustomerID variable to search orders
}
else if (OrderSearchType.GetType() == typeof(OrderSearchByOrderID))
{
OrderSearchByOrderID orderSearchByOrderID = (OrderSearchByOrderID)OrderSearchType;
string OrderID = orderSearchByOrderID.OrderID;
// User OrderID variable to search orders
}

return base.Execute(executionContext);
}


In Execute method, we first check OrderSearchType property value type, if it is OrderSearchByCustomerID then we convert it in that and find customer id which is assigned by user. If type is OrderSearchByOrderID then we convert it in that and find order id which is assigned by user.