HyperCard: Using Field-to-Message Feature (7/92)

There is a feature in HyperCard that allows you to pick up text and
transfer it to the message box. Holding the Command key down while the
cursor is in a field (locked or unlocked) will change the cursor to a hand
and draw a one-pixel selection box around the text. The selection box will
grow, one word at a time, as you drag through the text. When you release
the mouse button, the selected text will be placed in the message box.

This feature is hard-coded into HyperCard and can't be bypassed through
HyperTalk. First of all, in an unlocked field you will never be able to
retain the I-beam pointer (insertion point) when the Command key is down,
because some idle message will slip through to HyperCard creating a
blinking hand to I-beam cursor.

And you can't trap the mousedown in an unlocked field. However, even if you
try to trap the mousedown in a locked field and exit to HyperCard after
your defined action, the text will still be picked up and placed in the
message box.

This article is adapted from the Claris Tech Info database.