Static code blocks

Going from Java to C# I have the following question: In java I could do the following:

public class Application {
static int attribute;
static {
attribute = 5;
}
// ... rest of code
}

I know I can initialize this from the constructor but this does not fit my needs (I want to initialize and call some utility functions without create the object). Does C# support this? If yes, how can I get this done?

Thanks in advance,

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小开

最佳答案

public class Application
{


static int attribute;
static Application()
{
attribute = 5;
}    // removed
}

You can use the C# equivalent static constructors. Please don't confuse it with a regular constructor. A regular constructor doesn't have a static modifier in front of it.

I am assuming your //... rest of the code need to be also run once. If you don't have such code you can just simply do this.

 public class Application
{


static int attribute = 5;
}

小开

You just can write a static constructor block like this,

static Application(){
attribute=5;
}

This is what I could think of.

小开

In your particular scenario, you could do the following:

public class Application {
static int attribute = 5;
// ... rest of code
}

UPDATE:

It sounds like you want to call a static method. You can do that as follows:

public static class Application {
static int attribute = 5;


public static int UtilityMethod(int x) {
return x + attribute;
}
}

小开

I find something else useful. If your variable needs more than one expressions/statements to initialize, use this!

static A a = new Func<A>(() => {
// do it here
return new A();
})();

This approach is not limited on classes.

小开

-A static constructor doesn't have any parameter.
-A static class can contain only one static constructor.
-A static constructor executes first when we run the program.

Example:

namespace InterviewPreparation
{
public static class Program
{  //static Class
static Program()
{ //Static constructor
Console.WriteLine("This is static consturctor.");
}
public static void Main()
{ //static main method
Console.WriteLine("This is main function.");
Console.ReadKey();
}
}
}

Output:
This is static constructor.
This is main function.