If Class

Reference

Definition

Namespace:: System.Activities.Statements

Assembly:: System.Activities.dll

Important

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Models an If-Then-Else condition.

public ref class If sealed : System::Activities::NativeActivity

public sealed class If : System.Activities.NativeActivity

type If = class
    inherit NativeActivity

Public NotInheritable Class If
Inherits NativeActivity

Inheritance: Object

Activity

NativeActivity
If

Examples

The following code sample demonstrates creating an If activity.

new If
{
    // check if the order is asking for Widgets
    Condition = new InArgument<bool>( (e) => po.Get(e).PartName.Equals("Widget") ),
    Then = new If
    {
        // check if we have enough widgets in stock
        Condition = new InArgument<bool>( (e) => po.Get(e).Quantity < 100 ),
        Then = new SendReply
        {
            DisplayName = "Successful response",
            Request = submitPO,
            Content = SendContent.Create(new InArgument<string>( (e) => string.Format("Success: {0} Widgets have been ordered!", po.Get(e).Quantity)) )
        },
        // if we don't have enough widgets, throw an unhandled exception from this operation's body
        Else = new Throw
        {
            Exception = new InArgument<Exception>((e) => new Exception("We don't have that many Widgets."))
        }
    },
    // if its not for widgets, reply to the client that we don't carry that part by sending back an expected fault type (POFault)
    Else = new SendReply
    {
        DisplayName = "Expected fault",
        Request = submitPO,
        Content = SendContent.Create(new InArgument<FaultException<POFault>>( (e) => new FaultException<POFault>(
            new POFault
            {
                Problem = string.Format("This company does not carry {0}s, but we do carry Widgets.", po.Get(e).PartName),
                Solution = "Try your local hardware store."
            },
            new FaultReason("This is an expected fault.")
            )))
    }
}

Constructors

If()	Creates a new instance of the If class.
If(Activity<Boolean>)	Creates a new instance of the If class using the specified condition.
If(Expression<Func<ActivityContext,Boolean>>)	Creates a new instance of the If class using the specified condition.
If(InArgument<Boolean>)	Creates a new instance of the If class using the specified condition.

Properties

CacheId	Gets the identifier of the cache that is unique within the scope of the workflow definition. (Inherited from Activity)
CanInduceIdle	Gets or sets a value that indicates whether the activity can cause the workflow to become idle. (Inherited from NativeActivity)
Condition	The condition that determines which child activity to execute. The Then activity executes if the condition resolves to `true`. The Else activity executes if the condition resolves to `false`.
Constraints	Gets a collection of Constraint activities that can be configured to provide validation for the Activity. (Inherited from Activity)
DisplayName	Gets or sets an optional friendly name that is used for debugging, validation, exception handling, and tracking. (Inherited from Activity)
Else	The activity to be executed if the activity's Condition resolves to `false`.
Id	Gets an identifier that is unique in the scope of the workflow definition. (Inherited from Activity)
Implementation	The execution logic of the activity. (Inherited from NativeActivity)
ImplementationVersion	Gets or sets the implementation version of the activity. (Inherited from NativeActivity)
Then	The activity to be executed if the activity's Condition resolves to `true`.

Methods

Abort(NativeActivityAbortContext)	When implemented in a derived class, takes actions in response to the activity being aborted. (Inherited from NativeActivity)
CacheMetadata(ActivityMetadata)	Not implemented. Use the CacheMetadata(NativeActivityMetadata) method instead. (Inherited from NativeActivity)
CacheMetadata(NativeActivityMetadata)	Creates and validates a description of the activity's arguments, variables, child activities, and activity delegates. (Inherited from NativeActivity)
Cancel(NativeActivityContext)	When implemented in a derived class, runs logic to cause graceful early completion of the activity. (Inherited from NativeActivity)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
Execute(NativeActivityContext)	When implemented in a derived class, runs the activity's execution logic. (Inherited from NativeActivity)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity)	Raises an event when creating a map for the dynamic update. (Inherited from NativeActivity)
OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity)	Raises an event when creating a map for the dynamic update. (Inherited from NativeActivity)
ShouldSerializeDisplayName()	Indicates whether the DisplayName property should be serialized. (Inherited from Activity)
ToString()	Returns a String that contains the Id and DisplayName of the Activity. (Inherited from Activity)
UpdateInstance(NativeActivityUpdateContext)	Updates the instance of NativeActivity. (Inherited from NativeActivity)

Applies to

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