While Class

Reference

Definition

Namespace:: System.Activities.Statements

Assembly:: System.Activities.dll

Important

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Executes a contained activity while a condition evaluates to true.

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

[System.Windows.Markup.ContentProperty("Body")]
public sealed class While : System.Activities.NativeActivity

[<System.Windows.Markup.ContentProperty("Body")>]
type While = class
    inherit NativeActivity

Public NotInheritable Class While
Inherits NativeActivity

Inheritance: Object

Activity

NativeActivity
While

Attributes: ContentPropertyAttribute

Examples

The following code sample demonstrates creating a While activity.

new While
{
    Condition = true,
    Body = new Receive
    {
        ServiceContractName = Constants.POContractName,
        OperationName = Constants.UpdatePOName,
        CorrelatesWith = poidHandle, // identifies that the UpdatePO operation is waiting on the PurchaseOrderId that was used to initialize this handle
        CorrelatesOn = new MessageQuerySet // the query that is used on an incoming message to find the requisite PurchaseOrderId specified in the correlation
        {
            // Id is the name of the incoming parameter within the PurchaseOrder
            { "PoId", new XPathMessageQuery("sm:body()/defns:PurchaseOrder/defns:Id", Constants.XPathMessageContext) }
        },
        Content = ReceiveContent.Create(new OutArgument<PurchaseOrder>(po)) // creates a ReceiveMessageContent
    }
},

Constructors

While()	Creates a new instance of the While activity.
While(Activity<Boolean>)	Creates a new instance of the While activity.
While(Expression<Func<ActivityContext,Boolean>>)	Creates a new instance of the While activity.

Properties

Body	The Activity to execute in the `While` loop.
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 Activity<TResult> to be evaluated before each iteration of the `While` loop.
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)
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)
Variables	The collection of Variable objects associated with the While activity.

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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