Interaction between the UI thread and the working thread in WPF

In WPF, the interface objects in the UI thread cannot be modified by threads other than the UI. If you want to modify the interface object values in a non-UI thread, you can use system. windows. threading. invoke method in the dispatcher class

Public   Void Dowork ()
{
Threadpool. queueuserworkitem (waitcallback) Delegate ( Object O)
{ // In a non-UI thread
Bool Isconnected =   False ;
Dispatcher. Invoke (dispatcherpriority. Normal, (threadstart) Delegate ()
{
Writemessagetowin ("Cannot connect to server");
} );

}

  Private Textblock writemessagetowin ( String Message)
{
Tbtextblock. Text=Message;
}