vb.net - Getting a listbox item value safely in a thread -

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hi have program run threads , updates ui in process. have used .invokerequired safe threading , running ok. in 1 of threads necessary use value of item in listbox created in thread (listbox2.items(index)) , i'm doing dim item1 integer =listbox2.items(index). program running fine , showing no exceptions or error messages, however, if add watch of same line following message + accessibilityobject {"cross-thread operation not valid: control 'listbox2' accessed thread other thread created on."} system.invalidoperationexception.

is normal? there way safely value of item in listbox located on thread?

to answer question cross thread exception, normal , not allowed access ui elements different thread 1 created on. fix need use control.invoke() execute lambda expression run access code on thread created listbox.

dim item1 integer if listbox2.invokerequired     listbox2.invoke(sub() item1 = listbox2.items(index)) else     item1 = listbox2.items(index) end if

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