WPF TextBox - programatically select text while preserving "selection direction" -

While editing text, the user can use the keyboard shift button and direction keys to modify the selection - in a situation The anchor stays left by the other tricks, it is possible to obtain the running portion of the anchor portion on the left side.

I am trying to be dynamic, to modify the selection of users in the WPF text box (for the purposes of discussion, want to select characters in pairs, such as: pressing shift + left , 2 letters will not be selected for one, only). However, while selecting the selection / selection index / careindex / selection of "running end" is always selected at the right end of the selection, the change renders the left combination unusable.

Any way to preserve the "selection direction"?

This is not the answer that you want but this work. Invite the command and the way WPF does it.

  Editing Commands Select bedding Exquisite (empty, text box 1);