在C＃中创建一个类

Question

I have read the docs and everything but I'm very confused. I never needed to create a class before and now I do.

I want to have something like:

TextDocument.Save("filepath", "contents of file to save");

and stuff like:

Application.Create("filepath", "text/code to save");

and:

Stylesheet.Save("filepath", "contents");

and have these in a class and create methods for them but I'm very confused as to how to go about doing it can somebody please help me with this?

thank you, jase

Answer 1

Impossible to say without more code, but those look like static methods, ie create a new class (cs) file, and add something like:

using System.IO;
public class TextDocument {
   public static void Save(string path, string contents) {
       File.WriteAllText(path, contents);
   }
}

If TextDocument is actually an instance, take away the word static .

Note that to be callable, you also need to know about namespaces. The above is in the default namespace, but that is a bit vulgar. It should really be more like:

using System.IO;
namespace FooCorp.MagicApp {
    public class TextDocument {
        public static void Save(string path, string contents) {
            File.WriteAllText(path, contents);
        }
    }
}

Then only code with using FooCorp.MagicApp will see your class (this is a good thing for retaining sanity; there are lots of classes in the .NET framework)

Answer 2

public class Foo
{
   public static Foo Create()
   {
     //do stuff
   }

   public void Save()
   {
     //do stuff
   }
}

You call them differently, because of the static keyword

Foo f = Foo.Create();
f.Save();

and I recommend this book - http://oreilly.com/catalog/9780596003760

Note that create is really not the best static method in the world because of things called constructors, but for the sake of examples...

Answer 3

If you're confused to how classes and objects work, try to read a book (as Russell Steen points out ).

The terminology in tutorials and programming books may confuse beginners, if this is the case for you then try to fetch a programmer who does know and watch him code a class while asking as many questions you can until you get it . Programmers are generally a nice bunch of people.

If you really want to learn more about OOP (Object Oriented Programming), watch someone do some code kata or TDD.

Good luck writing your classes!

Answer 4

Yay! I created my first Class! :D hehehehe...

Here's the complete code. I don't know if it's the "best" way, or the most "efficient" way of doing this. But it works. I hope it can help others too:

using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;

namespace MyApp
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        public String FilePath,
            FileContents = null;

        public class TextDocument
        {
            public void Save(string FilePath, String FileContents)
            {
                File.WriteAllText(FilePath, FileContents);
            }
        }

        private void toolStripButton337_Click(object sender, EventArgs e)
        {
            FilePath = "this.txt";
            FileContents = "testing";

            TextDocument Document = new TextDocument();
            Document.Save(FilePath, FileContents);
        }
    }
}

Thank you Russell Steen and Marc Gravell for your help! :D