CS0120: An object reference is required for the nonstatic field, method, or property 'foo'

Question

Consider:

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            


        

Answer 1

Your method must be static

static void setTextboxText(int result)
{
    if (this.InvokeRequired)
    {
        this.Invoke(new IntDelegate(SetTextboxTextSafe), new object[] { result }); 
    }
    else
    {
        SetTextboxTextSafe(result);
    }
}