PowerBuilder HelpSelectText PowerScript function:
Syntax 1 For editable controls (except RichTextEdit)
Description

Selects text in an editable control. You specify where the selection begins and how many characters to select.

Controls

DataWindow, EditMask, MultiLineEdit, SingleLineEdit, DropDownListBox, and DropDownPictureListBox controls

Syntax

editname .SelectText ( start, length )

Argument Description
editname The name of the DataWindow, EditMask, MultiLineEdit, SingleLineEdit, DropDownListBox, or DropDownPictureListBox control in which you want to select text

start A long specifying the position at which you want to start the selection

length A long specifying the number of characters you want to select. If length is 0, no text is selected but PowerBuilder moves the insertion point to the location specified in start
Оно?

galileoЯ не уверен что PB предоставляет эту возможность.Возможно, я неправильно понял Ваш вопрос, но позицией курсора в редактируемом поле можно управлять именно так.
См. пример