C# calling public fields from a public static class

Question

I'm just learning C# after using VBA for many years, I'm not a professional and this is something I do in my leisure. I'm looking to replicate the logic of using a public variable that can be accessed from a method and incremented by one each time when clicking button cmdPublicVartest, Below is the code I have so far, but am getting the error An object reference is required for the non-static field , method, or property, in the publicvar class, it looks because it's a static class, however if I remove it from a static class, I would have to call an instance of the class on the button cmdPublicVartest. Is there a way I can keep publicvar a static class, so I don't have to do an instance of the class on the button?

namespace testDB
{
    public partial class Database : Form
    {
        public string publictest = "public test";
        public int pUblicint = 0;


         public static void   PublicVar()
        {
             
            MessageBox.Show(publictest + pUblicint);
            pUblicint++;

        }
        private void cmdPublicVartest_Click(object sender, EventArgs e)
        {
            testDB.Database.PublicVar();
        }
    }
}

Answer 1

You cannot access non-static fields from a static method because they belong to an instance of the class, and when calling a static method you do not have an instance.

You could either make the fields static like this

public partial class Database : Form
    {
        public static string publictest = "public test";
        public static int pUblicint = 0;


        public static void PublicVar()
        {

            MessageBox.Show(publictest + pUblicint);
            pUblicint++;

        }
        private void cmdPublicVartest_Click(object sender, EventArgs e)
        {
            testDB.Database.PublicVar();
        }
    }

Or make the method non-static like this

public partial class Database : Form
    {
        public string publictest = "public test";
        public int pUblicint = 0;


        public void PublicVar()
        {

            MessageBox.Show(publictest + pUblicint);
            pUblicint++;

        }
        private void cmdPublicVartest_Click(object sender, EventArgs e)
        {
            PublicVar();
        }
    }

Answer 2

Just revise your code to this:

namespace testDB
{
    public partial class Database : Form
    {
        public string publictest = "public test";
        public int pUblicint = 0;


        public void PublicVar()
        {
         
            MessageBox.Show(publictest + pUblicint);
            pUblicint++;

        }
        private void cmdPublicVartest_Click(object sender, EventArgs e)
        {
            PublicVar();
        }
    }
}

Answer 3

While PublicVar() is static, the fields it references ( publictest , pUblicint ) are not. You have to make them static as well or make PublicVar() not-static.