Blocked Property

Description

A True value indicates the control is currently executing a blocking method (Timeout is greater than 0), which has neither completed nor timed out with a ptTimeout error.

Property type

Read-only property

Syntax

Visual Basic
Public Property Blocked As Boolean

Remarks

Check this property to prevent your application from prematurely exiting or destroying the control while it is blocking in a method.

Your application still processes normal Windows messages while blocked, and the user interface continues to function normally. Events still fire while blocked, so code placed in these events continues to execute.

Your application cannot execute another method (except the Abort method) while it is blocked; a ptBlocked error is generated. Use the Abort method to terminate a blocked method prematurely. Abort signals the blocked method to abort, and then returns. Shortly thereafter, the blocked method releases all system resources, calls the State event (with the object's State property set to ptClosed), and returns with the ptAbort error.

WARNING Terminating your application or destroying the TCP object while blocked in a method may cause a fatal application error. To prevent this, perform either of the following:

Only allow object destruction if the Blocked property returns False.
Never use a positive Timeout value.