How could i let Resharper or Intellisense know that a method allwayse throws exception?

Question

I have an method that throws exception :

public void MyMethod()
{
    // do some logging
    throw new Exception("My Text");
}

I'm using this method in more than 100 places in my code, the problem is when i use this method in another method that must return a value Re-sharper dose not understands that there is no need for returning a value, for example :

public int AnotherMethod()
{
    // some stuff
    MyMethod(); // <= it always throws exception

    return 0; // i have to put this code, while it never executes
}

is there any way to tell Re-sharper that MyMethod is an exception just like this:

public int AnotherMethod()
{
    // some stuff
    throw new Exception(); // <= it always throws exception        
    //return 0; <= this line is no more needed
}

Answer 1

There's two issues here.

First, you can give ReSharper hints to code analysis, and I'll show you how below.

The problem here, however, is not ReSharper, but the compiler. The compiler will not be persuaded by these hints. The method you showed:

public int AnotherMethod()
{
    // some stuff
    MyMethod(); // <= it always throws exception

    return 0; // i have to put this code, while it never executes
}

Will have to be written like this even if you persuade ReSharper to understand that MyMethod always throws an exception. This has nothing to do with ReSharper, this is solely the C# compiler.

In order to tell ReSharper that your method behaves in a certain way, you can tag it with an attribute. You need to either copy a source code copy of those attributes into your project, or reference the ReSharper annotations assembly. Once you've done that, you can tag MyMethod like this:

[ContractAnnotation("=> halt")]
public void MyMethod()
...

However, again, the C# compiler will not care about this and will still complain about the missing return.

You can read more about the various attributes that ReSharper understands here: ReSharper Code Annotations Attributes.

Answer 2

You should not use an exception on a method like this, because exceptions are meant to raise WHEN a method could not achive its goal because of EXCEPTIONAL conditions, not ALWAYS.

You should use a custom exception like

public class MyException():Exception
{ 
    public MyException(): base("Your text goes here")
    {
        // do some logging
    }
}

You could also add properties to your custom exception class, and hold additional information on them like

public class MyException():Exception
{ 
    public long Id { get; set; }

    public MyException(long id): base("Your text goes here")
    {
        this.Id = id;
        // and do some logging
    }
}