Artikel
05/23/2011

Variables Class

Contains a collection of Variables objects, which are accessed through several objects. This class cannot be inherited.

Inheritance Hierarchy

System.Object
Microsoft.SqlServer.Dts.Runtime.DTSReadOnlyCollectionBase
Microsoft.SqlServer.Dts.Runtime.Variables

Namespace: Microsoft.SqlServer.Dts.Runtime
Assembly: Microsoft.SqlServer.ManagedDTS (in Microsoft.SqlServer.ManagedDTS.dll)

Syntax

'Declaration
Public NotInheritable Class Variables _
    Inherits DTSReadOnlyCollectionBase
'Usage
Dim instance As Variables

public sealed class Variables : DTSReadOnlyCollectionBase

public ref class Variables sealed : public DTSReadOnlyCollectionBase

[<SealedAttribute>]
type Variables =  
    class
        inherit DTSReadOnlyCollectionBase
    end

public final class Variables extends DTSReadOnlyCollectionBase

The Variables type exposes the following members.

Properties

	Name	Description
	Count	Gets the number of elements contained in the DTSReadOnlyCollectionBase instance. (Inherited from DTSReadOnlyCollectionBase.)
	IsSynchronized	Gets a value that indicates whether access to the DTSReadOnlyCollectionBase is synchronized (thread-safe). (Inherited from DTSReadOnlyCollectionBase.)
	Item	Returns a Variable object from the Variables collection.
	Locked	A Boolean indicating whether the variables in the Variables collection are locked.
	SyncRoot	Gets an object that can be used to synchronize access to the DTSReadOnlyCollectionBase. (Inherited from DTSReadOnlyCollectionBase.)

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Methods

	Name	Description
	Add	Adds a Variable object to the Variables collection.
	Contains	Returns a Boolean that indicates whether the items in the collection can be accessed by using indexing without throwing an exception.
	CopyTo	Copies the entire DTSReadOnlyCollectionBase to a compatible one-dimensional array, starting at the specified index of the target array. (Inherited from DTSReadOnlyCollectionBase.)
	CreateManagedObject	Infrastructure. (Inherited from DTSReadOnlyCollectionBase.)
	Equals	(Inherited from Object.)
	Finalize	(Inherited from Object.)
	GetCount	Infrastructure. (Inherited from DTSReadOnlyCollectionBase.)
	GetEnumerator	Returns a VariableEnumerator enumerator for use in iterating over the Variables collection.
	GetHashCode	(Inherited from Object.)
	GetManagedEnumerator	Infrastructure. (Inherited from DTSReadOnlyCollectionBase.)
	GetType	(Inherited from Object.)
	MemberwiseClone	(Inherited from Object.)
	Remove	Removes a Variable object from the Variables collection.
	ToString	(Inherited from Object.)
	Unlock	Releases the locks on the variables collection and flags the state of the variables collection as invalid or unknown.

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Fields

	Name	Description
	m_unmanagedColl	Infrastructure. (Inherited from DTSReadOnlyCollectionBase.)

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Remarks

Integration Services (SSIS) provides system variables and supports custom user variables. When you create a new package, add a container or a task to the package, or create an event handler, SSIS automatically includes a set of system variables for the item. System variables are always located in the System namespace. System variables contain useful information about the package and its containers, tasks, and event handlers. System variables contain information such as the name of the computer on which the package runs and the time the package starts. You can view the information that is contained in a system variable, but you cannot add to or update system variables.

You can also create custom variables for use in packages, containers, tasks, transformations, and precedence constraints. Custom variables can be created in the User namespace or a namespace of your choice. Custom variables can be used in the expressions that the For Loop container, the Derived Column transformation, the Conditional Split transformation, and precedence constraints may contain. For more information, see Using Variables in Packages.

Every container in the SSIS object model has a Variables collection. This collection is accessible to each child of the container. A variable is accessed from the collection by using its name or its index. The Variables collection on a container represents an aggregation of the variables in the collection of its parent. The Variables collection of the Package class is visible to all objects in the package, providing a globally visible collection. Conversely, the variables contained in a task are limited in scope and visibility, and are only visible by the task.

Important

The Variables is used with the Runtime classes. If you are using data flow components (Microsoft.SqlServer.Dts.Pipeline), you may be required to use the IDTSVariables100. To know which variables collection to use, see the documentation for the object you are acquiring variables on, and verify the return value.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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