Export (0) Print
Expand All

VariableDispenser Class

Accesses the Variables collection during package execution. This class cannot be inherited.

Object
  Microsoft.SqlServer.Dts.Runtime.DtsObject
    Microsoft.SqlServer.Dts.Runtime.VariableDispenser

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

public sealed class VariableDispenser : DtsObject

The VariableDispenser type exposes the following members.

  NameDescription
Public methodContainsSpecifies whether an item can be retrieved from the VariableDispenser collection by using indexing without throwing an exception.
Public methodEqualsDetermines whether two object instances are equal. (Inherited from DtsObject.)
Public methodGetHashCodeReturns the hash code for this instance. (Inherited from DtsObject.)
Public methodGetQualifiedNameReturns the qualified name of the variable.
Public methodGetType (Inherited from Object.)
Public methodGetVariablesLocks the variables that are in the read-only list and the read/write list.
Public methodLockForReadAdds the variable to the list of variables to be locked for read-only access.
Public methodLockForWriteAdds the variable to the list of variables to be locked for read/write access.
Public methodLockOneForReadPuts the variable in a list, and then locks it for read-only access.
Public methodLockOneForWritePuts the variable in a list, and then locks it for read/write access.
Public methodResetClears both the read-only list and read/write list when the call to GetVariables fails.
Public methodToString (Inherited from Object.)
Top

There are two scenarios for using the variable dispenser.

  1. You want just one variable. In this scenario, call LockOneForRead or LockOneForWrite, and a collection with one element is returned.

  2. You want several variables. In this scenario, call LockForRead and LockForWrite several times, one for each variable. This builds up two lists, one list that contains variables for reading and one list that contains variables for writing. Next, call GetVariables, which gives you a collection that contains all of the locked variables. If GetVariables succeeds, the two lists, which are the lists of variable names, not actual locks, are cleared.

To explicitly release the locks, call Unlock on the collection. This method unlocks the variables themselves. If GetVariables fails, the lists remain unchanged, and you can call GetVariables again. If you still do not succeed in obtaining the variables, call Reset to clear the lists and bring the variable dispenser back to its initial state.

The Variables collection contains a Locked property that indicates whether a variable dispenser collection of variables is locked (true) or unlocked (false). The reason to review this property is that some tasks explicitly release locks to the variables they are using, and calling Unlock twice throws an error. Therefore, you should use this property to determine whether the dispensed collection is locked before calling Unlock.

Important noteImportant

The VariableDispenser is used with the Runtime classes. If you are using data flow components (Microsoft.SqlServer.Dts.Pipeline), then you may be required to use the IDTSVariableDispenser100 instead. To know which variable dispenser to use, see the documentation for the object you are acquiring variables on, and verify the return object of the method.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft