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richardking4
2,997 PointsSystem.NullReferenceException, filename unknown (Tower Defense project)
Hello all — I'm getting the following error when running my code:
Unhandled exception reads: System.NullReferenceException: Object reference not set to an instance of an object at TreehouseDefence.Game.Main () <0x4087fd50 + 0x0041b> in <filename unknown>:0
It compiles just fine. Here's a snapshot:
I guess I have two questions:
1) Why am I not getting details on where this exception is stemming from? Even if I run the compiler using -debug I don't get any extra details. All I can work out is that it's coming from somewhere within the try ... catch block in my Main() method.
2) What part did I mess up?? Hah.
1 Answer
Steven Parker
231,236 PointsI was able to replicate your message by running "Game.exe", but I noticed that it had been built before the last edit to "Game.cs".
So I rebuilt the project and when I run that, I get no error. So it seems you'd already fixed the issue in the source but just had not rebuilt yet.
richardking4
2,997 Pointsrichardking4
2,997 PointsYou won't believe it...
I've been running this to compile for a while:
clear && mcs -out:Game.exe *.cs && mono Game.exe
But then I got lazy and started running it as:
clear && mcs *.cs && mono Game.exe
...little realising that we'd subsequently added Exceptions.cs in the videos and it was now compiling as Exceptions.exe... :)
Oops. Thanks for taking the time to look, now I'll know to check that!
Steven Parker
231,236 PointsSteven Parker
231,236 PointsI just figured that other executable was from some extra-curricular experimentation.
Happy coding!