Класс Variables

Статья
04/26/2013

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

Иерархия наследования

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

Пространство имен: Microsoft.SqlServer.Dts.Runtime
Сборка: Microsoft.SqlServer.ManagedDTS (в Microsoft.SqlServer.ManagedDTS.dll)

Синтаксис

'Декларация
Public NotInheritable Class Variables _
    Inherits DTSReadOnlyCollectionBase
'Применение
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

Тип Variables обеспечивает доступ к следующим элементам.

Свойства

	Имя	Описание
	Count	Gets the number of elements contained in the DTSReadOnlyCollectionBase instance. (Производный от DTSReadOnlyCollectionBase.)
	IsSynchronized	Gets a value that indicates whether access to the DTSReadOnlyCollectionBase is synchronized (thread-safe). (Производный от 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. (Производный от DTSReadOnlyCollectionBase.)

В начало

Методы

	Имя	Описание
	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. (Производный от DTSReadOnlyCollectionBase.)
	Equals	(Производный от Object.)
	GetEnumerator	Returns a VariableEnumerator enumerator for use in iterating over the Variables collection.
	GetHashCode	(Производный от Object.)
	GetType	(Производный от Object.)
	Join	Joins the Variable to the Variables collection.
	Remove	Removes a Variable object from the Variables collection.
	ToString	(Производный от Object.)
	Unlock	Releases the locks on the variables collection and flags the state of the variables collection as invalid or unknown.

В начало

Замечания

Службы Integration Services (Службы 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, Службы 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 Использование переменных в пакетах.

Every container in the Службы 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.

Важно!
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.

Безопасность многопоточности

Любые открытые статический (Shared в Visual Basic) элементы этого типа потокобезопасны. Потокобезопасность с элементами экземпляров не гарантируется.

См. также

Справочник

Пространство имен Microsoft.SqlServer.Dts.Runtime

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