Windows forms different classes, trying to change textbox.text

Question

Im trying to make a function that fetches the data from my settings file (HighscoreSaved wich is put into highscoreList array) and then join the strings and write them into the textbox (highScore.Text)

However when i call on the function nothing happens

So here is my code: Form1

private void button4_Click_1(object sender, EventArgs e)
    {
        Highscore.Fetch();
        Highscore.Set();
    }

    public void highscoreText (string value)
    {
            this.highScore.Text = value;
    }

And heres the class thats supposed to be called by Highscore.Fetch(), and Highscore.Set() But when i call on them nothing changes in my textbox

public static class Highscore
    {
        public static void  Fetch()
        {
            Form1.highscoreList[0] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper1 + "\t\t" + HighscoreSaved.Default.highscoreScore1;
            Form1.highscoreList[1] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper2 + "\t\t" + HighscoreSaved.Default.highscoreScore2;
            Form1.highscoreList[2] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper3 + "\t\t" + HighscoreSaved.Default.highscoreScore3;
            Form1.highscoreList[3] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper4 + "\t\t" + HighscoreSaved.Default.highscoreScore4;
            Form1.highscoreList[4] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper5 + "\t\t" + HighscoreSaved.Default.highscoreScore5;
            Form1.highscoreList[5] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper6 + "\t\t" + HighscoreSaved.Default.highscoreScore6;
            Form1.highscoreList[6] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper7 + "\t\t" + HighscoreSaved.Default.highscoreScore7;
            Form1.highscoreList[7] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper8 + "\t\t" + HighscoreSaved.Default.highscoreScore8;
            Form1.highscoreList[8] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper9 + "\t\t" + HighscoreSaved.Default.highscoreScore9;
            Form1.highscoreList[9] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper10 + "\t\t" + HighscoreSaved.Default.highscoreScore10;

            Form1.highscoreInt[0] = HighscoreSaved.Default.highscoreScore1;
            Form1.highscoreInt[1] = HighscoreSaved.Default.highscoreScore2;
            Form1.highscoreInt[2] = HighscoreSaved.Default.highscoreScore3;
            Form1.highscoreInt[3] = HighscoreSaved.Default.highscoreScore4;
            Form1.highscoreInt[4] = HighscoreSaved.Default.highscoreScore5;
            Form1.highscoreInt[5] = HighscoreSaved.Default.highscoreScore6;
            Form1.highscoreInt[6] = HighscoreSaved.Default.highscoreScore7;
            Form1.highscoreInt[7] = HighscoreSaved.Default.highscoreScore8;
            Form1.highscoreInt[8] = HighscoreSaved.Default.highscoreScore9;
            Form1.highscoreInt[9] = HighscoreSaved.Default.highscoreScore10;

            Form1.highscoreKeeper[0] = HighscoreSaved.Default.highscoreKeeper1;
            Form1.highscoreKeeper[1] = HighscoreSaved.Default.highscoreKeeper2;
            Form1.highscoreKeeper[2] = HighscoreSaved.Default.highscoreKeeper3;
            Form1.highscoreKeeper[3] = HighscoreSaved.Default.highscoreKeeper4;
            Form1.highscoreKeeper[4] = HighscoreSaved.Default.highscoreKeeper5;
            Form1.highscoreKeeper[5] = HighscoreSaved.Default.highscoreKeeper6;
            Form1.highscoreKeeper[6] = HighscoreSaved.Default.highscoreKeeper7;
            Form1.highscoreKeeper[7] = HighscoreSaved.Default.highscoreKeeper8;
            Form1.highscoreKeeper[8] = HighscoreSaved.Default.highscoreKeeper9;
            Form1.highscoreKeeper[9] = HighscoreSaved.Default.highscoreKeeper10;                
        }
        public static void Set()
        {
            Form1 mainForm = new Form1();
            string[] highscoreImported = new string[10];
            Array.Copy(Form1.highscoreList, highscoreImported, 10);
            string highscores = string.Join("\n", highscoreImported);
            mainForm.highscoreText(highscores);
        }

Answer 1

You are creating a new instance of the Form1 in your Set method , that is why you are not seeing the change. You should pass an instance of the Form to the method instead.

Something like (in your class Highscore) :

public static void Set(Form mainForm)
{
    string[] highscoreImported = new string[10];
    Array.Copy(Form1.highscoreList, highscoreImported, 10);
    string highscores = string.Join("\n", highscoreImported);
    mainForm.highscoreText(highscores);
}

Later you can call it like:

private void button4_Click_1(object sender, EventArgs e)
{
    Highscore.Fetch();
    Highscore.Set(this); //notice "this"
}

Answer 2

A better approach would be to do all of them at one go.

using System.Linq;

public static void  FetchAndSet()
{
    Form1.highscoreList[0] = "\t\t\t" + HighscoreSaved.Default.highscoreKeeper1;
    .
    .

    Form1.highscoreInt[0] = HighscoreSaved.Default.highscoreScore1;
    .
    .

    Form1.highscoreKeeper[0] = HighscoreSaved.Default.highscoreKeeper1;
    .
    .

    //Use LINQ's Take to Pull out the Top 10.   
    string highscores = string.Join("\n", highscoreList.Take(10));
    this.highscoreText(highscores);     
}