With block equivalent in C#?

Although C# doesn't have any direct equivalent for the general case, C# 3 gain object initializer syntax for constructor calls:

var foo = new Foo { Property1 = value1, Property2 = value2, etc };

See chapter 8 of C# in Depth for more details - you can download it for free from Manning's web site.

(Disclaimer - yes, it's in my interest to get the book into more people's hands. But hey, it's a free chapter which gives you more information on a related topic...)

This is what Visual C# program manager has to say: Why doesn't C# have a 'with' statement?

Many people, including the C# language designers, believe that 'with' often harms readability, and is more of a curse than a blessing. It is clearer to declare a local variable with a meaningful name, and use that variable to perform multiple operations on a single object, than it is to have a block with a sort of implicit context.

As the Visual C# Program Manager linked above says, there are limited situations where the With statement is more efficient, the example he gives when it is being used as a shorthand to repeatedly access a complex expression.

Using an extension method and generics you can create something that is vaguely equivalent to a With statement, by adding something like this:

    public static T With<T>(this T item, Action<T> action)
    {
        action(item);
        return item;
    }

Taking a simple example of how it could be used, using lambda syntax you can then use it to change something like this:

    updateRoleFamily.RoleFamilyDescription = roleFamilyDescription;
    updateRoleFamily.RoleFamilyCode = roleFamilyCode;

To this:

    updateRoleFamily.With(rf =>
          {
              rf.RoleFamilyDescription = roleFamilyDescription;
              rf.RoleFamilyCode = roleFamilyCode;
          });

On an example like this, the only advantage is perhaps a nicer layout, but with a more complex reference and more properties, it could well give you more readable code.

About 3/4 down the page in the "Using Objects" section:

VB:

With hero 
  .Name = "SpamMan" 
  .PowerLevel = 3 
End With

C#:

//No "With" construct
hero.Name = "SpamMan"; 
hero.PowerLevel = 3;

With block equivalent in C#?

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