.NET Framework 4.6 and 4.5
Specifies the value of the TransactionAttribute.
Assembly: System.EnterpriseServices (in System.EnterpriseServices.dll)
|The isolation level for the component is obtained from the calling component's isolation level. If this is the root component, the isolation level used is .|
|Shared locks are held while the data is being read to avoid reading modified data, but the data can be changed before the end of the transaction, resulting in non-repeatable reads or phantom data.|
|Shared locks are issued and no exclusive locks are honored.|
|Locks are placed on all data that is used in a query, preventing other users from updating the data. Prevents non-repeatable reads, but phantom rows are still possible.|
|Prevents updating or inserting until the transaction is complete.|
The following code example demonstrates the use of the type.
Imports System Imports System.EnterpriseServices Imports System.Reflection ' References: ' System.EnterpriseServices ' An instance of this class will inherit its caller's transaction isolation ' level if available. If not, it will use isolation level Serializable. <Transaction(Isolation := TransactionIsolationLevel.Any)> _ Public Class TransactionAttribute_IsolationAny Inherits ServicedComponent End Class 'TransactionAttribute_IsolationAny ' An instance of this class will read only committed data, but non-repeatable ' reads and phantom rows are still possible. <Transaction(Isolation := TransactionIsolationLevel.ReadCommitted)> _ Public Class TransactionAttribute_IsolationReadCommitted Inherits ServicedComponent End Class 'TransactionAttribute_IsolationReadCommitted ' An instance of this class will read committed and uncommitted data, so dirty ' reads, non-repeatable reads, and phantom rows are possible. <Transaction(Isolation := TransactionIsolationLevel.ReadUncommitted)> _ Public Class TransactionAttribute_IsolationReadUncommitted Inherits ServicedComponent End Class 'TransactionAttribute_IsolationReadUncommitted ' An instance of this class will read only committed data and place shared ' locks on the data, preventing other users from modifying it, but other users ' can still insert rows into the data set, so phantom rows are still possible. <Transaction(Isolation := TransactionIsolationLevel.RepeatableRead)> _ Public Class TransactionAttribute_IsolationRepeatableRead Inherits ServicedComponent End Class 'TransactionAttribute_IsolationRepeatableRead ' An instance of this class will read only committed data and place a range ' lock on the data set, preventing other users from updating or inserting rows ' into the data set until its transaction is complete. <Transaction(Isolation := TransactionIsolationLevel.Serializable)> _ Public Class TransactionAttribute_IsolationSerializable Inherits ServicedComponent End Class 'TransactionAttribute_IsolationSerializable