ExistsInCollection<T> Activity Designer

The ExistsInCollection<T> activity designer is used to create and configure an ExistsInCollection<T> activity.

The ExistsInCollection<T> Activity

The ExistsInCollection<T> activity determines whether a specified item exists in a particular collection.

Using the ExistsInCollection<T> Activity Designer

The ExistsInCollection<T> activity designer can be found in the Collection category of the Toolbox, which is accessed by clicking the Toolbox tab of Workflow Designer (Alternatively, select Toolbar from the View menu or CTRL+ALT+X.)

The ExistsInCollection<T> activity designer can be dragged from the Toolbox and dropped on to the Workflow Designer surface wherever activities are usually placed, such as inside a Sequence. This creates a ExistsInCollection<T> activity with a default DisplayName of ExistsInCollection<Int32>. (By default, the TypeArgument is Int32. It can be changed in the property grid.) The DisplayName value can be edited in the header of the ExistsInCollection<T> activity designer or in the DisplayName box of the property grid. The other properties must be edited on the property grid.

The ExistsInCollection<T> Properties

The following table shows the ExistsInCollection<T> properties and describes how they are used in the designer.

Property Name Required Usage
DisplayName False The friendly name of the ExistsInCollection<T> activity. The default is ExistsInCollection<Int32>. Although the DisplayName value is not strictly required, it is a best practice to use one.
Item True The item to add to the Collection<T>. This item is of type T is of type TypeArgument. To specify the item, type a Visual Basic expression in the property grid.
Collection True The collection to which the item should be added. This collection is of type ICollection<TypeArgument>. To specify the collection, type a Visual Basic expression in the property grid.
TypeArgument True The type T of the items contained in the ICollection<T>. By default, this TypeArgument type is set to Int32. To change the type, change the value of the TypeArgument in the combo box in the property grid.
Result False A value that indicates whether the specified item exists in the collection. To specify a variable to bind to the result, type a Visual Basic variable in the property grid.

See Also

Collection AddToCollection<T> ClearCollection<T> RemoveFromCollection<T>