SetProperty - GetProperty "text"

Ladies and Gentlemen,
I try to migrate my Lisp for ACAD2015 using runtime 8.0.0.15.
Now I have a problem with SetProperty btw. GetProperty.
Depending on the choice in a listfield a value has to be inserted in a textfield, this works fine with SetProperty "text".
The user now has the opportunity to change this value.
In the main programm I want to read this value per GetProperty "text", but this doesnt work...
Can somebody help me with this challenge?
Thanks!

Have to tried "(dcl-Control-GetText )" to read from a text-field (see help). Usually, I try to avoid the "Getproperty-Feature" - for me it is more complicated than the directly working "Getxxx-Features".