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VariableDispenser.LockOneForRead(String, Variables) Method

Definition

Puts the variable in a list, and then locks it for read-only access.

public:
 void LockOneForRead(System::String ^ variable, Microsoft::SqlServer::Dts::Runtime::Variables ^ % variables);
public void LockOneForRead (string variable, ref Microsoft.SqlServer.Dts.Runtime.Variables variables);
member this.LockOneForRead : string * Variables -> unit
Public Sub LockOneForRead (variable As String, ByRef variables As Variables)

Parameters

variable
String

The variable you want to lock for read-only access.

variables
Variables

The name of the variables collection to put the requested variable into.

Remarks

This method combines the work of the LockForRead method and the GetVariables method in one call, because it applies to a single variable only.

If the call succeeds, the requested variable is returned as a one-entry collection in the variable collection specified by the parameter variables, and the variable is locked for read-only access. To unlock the variable, release the variable collection by using the Unlock method of the Variables class. If the call to the LockOneForRead method fails, the variable is not locked.

Calls to this method do not affect the lock list generated via calls to LockForRead.

Note

It is recommended that you do not make multiple calls to this method when acquiring locks for variables to be used together because this could lead to deadlocks. All variables being used together should be requested and locked together by using the methods LockForRead or LockForWrite, followed by a call to GetVariables.

If a lock was successful, you can clear it by calling Unlock.

Applies to