Visual Studio

An IDE for the .NET stack

Debugging

Data Breakpoints

Data breakpoints are used to halt when a variable's value changes

They can be enabled by right-clicking on a variable in the Autos/Locals/Watch window and selecting "Enable Data Breakpoint". The next time that variable changes, the debugger will halt and show you the changes value

[DebuggerDisplay]

The DebuggerDisplay attribute can be used to alter how the debugger shows variables

Add [DebuggerDisplay] to external types

ClassLibrary1

//using System.Diagnostics;

namespace ClassLibrary1
{
    //[DebuggerDisplay("Foo.Bar={Bar}")] // works too for types you own
    public class Foo
    {
        private int Bar = 42;
    }
}

ConsoleApp1

using System.Diagnostics;
using System.Reflection;
using ClassLibrary1;

[assembly: DebuggerDisplay("Foo.Bar={FooDebuggerDisplay.Bar(this)}", Target=typeof(Foo))]

class FooDebuggerDisplay
{
    public static int Bar(Foo foo) => (int)foo.GetType().GetField("Bar",BindingFlags.Instance|BindingFlags.NonPublic).GetValue(foo);
}

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var foo = new Foo();
            Debugger.Break();
        }
    }
}

CC-BY-SA Jens

Customizing the Call Stack

You are able to customize the call stack window by right clicking on an item

View Value Returned by a Function

Step to the end closing bracket and view the Autos window, there should be a value that ends with 'returned'. Or you can add $ReturnValue to the watch window.

Format Specifiers can be applied to the $ReturnValue to alter how it is displayed in the output window.

Step into Specific

Allows you to step directly into nested function calls

Trigger an Exception

Use the Immediate Window to set a nullable variables value to null, use that to trigger a null reference exception when stepping though code

Format Specifiers (C#)

Format specifiers can be applied to any variable debugging display, such as the watch window or immediate window. To use a format specifier, enter the varible specifier followed by a comma and then the format specifier. stringWhoShallNotBeNamed,nq

• nq

  Removes quotes from the displayed string

• nse

  Specifies that the expression should be evaluated with no side effects if possible. If the expression must be evaluated instead of interpreted, an error will be shown.

• hidden

  Includes hidden members in the output.

• results

  For use with IEnumerable and IEnumnerable<T> types. Displays the results of the query expresion.

FAQ

Missing errors in the Editor or Error List

Try deleting the .sou file located at <SolutionFolder>\.vs\<ProjectName>\v16\.sou.

The .sou file contains user-defined solution settings, such as breakpoints and debug options. It can sometimes become corrupted causing erratic behavior.

The file will get recreated when reloading the solution.