I have written a couple of delphi components to accept input of various types of data.

You will find the source code at bitbucket.org/dhsoftware/datacad-components/src/master/.

Or download the compiled Package Library file here. (Updated 26 March 2019)

There is no documentation, but briefly:

The DcadNumericEdit component allows for the entry of distances (using the current scale type setting for the input), angles, and integer or floating point numbers. You set the input type using the NumberType property and use the NumValue property to access the distance/angle/floating point number, or the IntValue to access an integer number. Note that you should check the Valid property as well as the NumValue or IntValue properties as these properties will return zero if the input is not valid for the type of number chosen.
(The standard text property can still be used to access the actual text in the component.)

The DcadEdit component is pretty much the same, but allows you to use the same component to enter free-format text (actually you could use this component in place of the DcadNumericEdit component simply by setting the appropriate NumberType property, so the DcadNumericEdit component is no longer really required).