ToString() method

Question

Book says A class's ToString() method is often a useful debugging aid. Any one knows please show how it can be used to debug.

Sam Hobbs · Answer

No they are not free. Only the Express editions are free. You can do nearly the same thing by adding an item to the watch window. Please learn about that. Note that when I first learned about these things the internet was not available for getting help like this. The watch window is something that the MSDN is enough for learning about it and there are many articles available to help you. Just look for articles about the watch window.

Maha · Answer

I come to know from the website you were given that C# Pro and Team edition will support the QuickWatch Window. I wish to know is there any website provides free download of this software.

Vulpes · Answer

You mentioned in a previous thread that you were using VC# Express 2010 which doesn't support the QuickWatch window so you can forget about it for now. However for future reference there's a bit about it here in the MSDN docs: http://msdn.microsoft.com/en-us/library/cyzbs7s2.aspx

Maha · Answer

I don't know anything about quickwatch window. Could you tell me where to begin from.

Sam Hobbs · Answer

There is one article in this web site about debugging that does not use the terms single-step and step-over; it uses some other terms that are not commonly used. I posted a comment to the article saying so but the author did not understand what I was trying to say. Anyway in the Debug menu is Step Into (F11) which is often called single-step since it executes one line of code each time. Also there is Step Over (F10) since it will execute a method without going into it for debugging. If you use single-step when a method is called then the debugger will go to the first executable line in the method and then you can see what happens in the method. There is also Step Out (Shift-F11) which will finish executing a method and break at the first line afer the method call. If you are not familiar with these or if any of this is confusing then find articles about these things. The quickwatch window is also very useful. I use it a lot. If you do not know what the quickwatch window is then learn about that. Also learn about the watch window which is different from the quickwatch window. Perhaps the most important debugging technique is breakpoints; simple breakpoints can be toggled for a line using F9. It is also possible to set a breakpoint that is conditional such as a when a variable changes in value. I have never used that for C# but it can be very useful. At the top of the Debug menu is Windows. You should look at what is there. The Locals window is something I used a lot for C++ but it can be useful for C# too. The call stack can also be useful. Also Debug.Print can be useful. It is like Console.WriteLine but it works for GUI programs too. It is a convenient way to show data during execution that you can look at after debugging. Those are nearly all the debugging tools I commonly use. They are all I can think of now.

Vulpes · Answer

We do have some good articles on debugging on this site: http://www.c-sharpcorner.com/Search/?sKeywords=debugging However this one on Code Project which relates to VS 2010 specifically is probably as good a tutorial as you'll find: http://www.codeproject.com/KB/cs/MasteringInDebugging.aspx

Maha · Answer

Book I use is not providing enough information about debugging. At the moment I am heavily depend on YouTube. I wish to know is there any website teaching about debugging from the beginning.

Vulpes · Answer

If you don't have a dedicated debugger then what is an aid to debugging is the Console.WriteLine or Debug.WriteLine methods to tell you the state of variables at the time. When presented with arguments which are not strings these methods automatically call the ToString() method of the argument's type. However unless you're always going to be interested in the same bunch of variables you might as well specify the variables individually rather than roll them up into a ToString() overload.

Sam Hobbs · Answer

It is true. The ToString() method is often a useful debugging aid. The default implementation is not very useful; the same result can be obtained using GetType.FullName (or GetType.Name; something like that). The Object.ToString Method says you should override the ToString method to return values that are meaningful for those types. So for objects with a meaningful ToString override ToString is a very convenient way to show the data for many purposes including diagnostic. The only unusual thing about what the book says is that it emphasizes debugging relative to all the other useful purposes of ToString.

Maha · Answer

Thank you for your explanation.

Vulpes · Answer

Yes it does say that but unfortunately doesn't offer any explanation.

Maha · Answer

Yes this is from the same book. I attach the page.

Vulpes · Answer

If this is the same book at you normally use it's again coming up with some strange remarks. The ToString() method which all classes inherit from System.Object by default returns the name of the type though it can be overridden to return anything you like. I suppose you could override it to return a combination of the values of various properties which might be useful for debugging purposes but why anyone would want to do that when we have Visual Studio's built-in debugger available I don't know.