Connecting DB25 socket to protoboard/breadboard
What about using a short length of ribbon cable to combine a DB25 IDC connector

with a 28-pin IDC DIP socket


Clamping the IDC parts onto the ribbon cable takes a little care (make sure the 'knives' are correctly lined up over the wires in the ribbon), but I've done it in a small bench vice many times with a better than 99% success rate.