Convert existing event handler invocations to C#6 Null Propagation

Search for:

if \(handler \!= null\)\s*\r?\n\s*\{\r?\n\s*handler\((?<args>.*?)\);\r?\n\s*\}

and replace using:

handler?.Invoke(${args});

For example, this will be matched and replaced

if (handler != null)
{
    handler(this, new DialogResponseEventArgs(id, true));
}

with this

handler?.Invoke(this, new DialogResponseEventArgs(this.dialogCorrelationId, message.Response == ShellDialogButton.Cancel));

Converting existing code to use C#6 Expression Bodied Properties

Converting all types of Simple Properties

Search for

[^\S\r\n]+(?<accessor>\w+)(?<override> override | )(?<typename>\w+) (?<pname>.*?)\r?\n\s*\{\r?\n\s*get(\r?\n)*\s*\{\s*return (?<returnexpr>.*?);\s*\}\s*\}

and replace with

${accessor} ${override}${typename} ${pname} => ${returnexpr};

For example the following properties will be matched and converted:

public override string Description 
{
    get 
    {
        return "The quick brown fox jumped over the lazy dog.";
    }
}

public string Description 
{
    get 
    {
        return "The quick brown fox jumped over the lazy dog.";
    }
}

public string Description 
{
    get { return "The quick brown fox jumped over the lazy dog."; }
}

public bool HasValue 
{
    get { return this.field; }
}

public virtual IEnumerable<BudgetBucket> Buckets
{
    get { return this.lookupTable.Values.OrderBy(b => b.Code).ToList(); }
}

All the above are changed to the new syntax:

public override string Description => "The quick brown fox jumped over the lazy dog.";

Converting existing code to use nameof() in C# 6

Now with the new C#6 nameof operator, the use of ArgumentNullExceptions and ArgumentExceptions become more flexible and resistant to variable refactoring and renaming.

ArgumentNullException

Here's a regex to search and replace in Visual Studio usage of ArgumentNullException: Search for:

throw new ArgumentNullException("(?<message>.*?)

Replace with:

throw new ArgumentNullException(nameof(${varname})

For example this will replace this

throw new ArgumentNullException("variable", "This variable cannot be null.");

with

throw new ArgumentNullException(nameof(variable), "This variable cannot be null.");

ArgumentException

Here's another regex to search and replace usage of ArgumentException: Search for:

throw new ArgumentException\("(?<message>.*?)", "(?<varname>.*?)"

Replace with:

throw new ArgumentException("${message}", nameof(${varname})

For example this will replace this

throw new ArgumentException("This argument is invalid for some weird reason.", "variable");

with

throw new ArgumentException("This argument is invalid for some weird reason.", nameof(variable));