How do I Set A TextBox's Minimum String

I know how to set a textbox's max string Here

but how do I set the minimum characters it can have?

now I know the backspace deletes the whole text if it is highlighted.

so I need a way around this.

change from less than to greater than?

nope but I found out how to do

when your textbox input is between or equal the max and the min

set a var to the textboxes text

if it is greater the the max or lesser then the min

set the textboxes text to the var