Strange of prefix decrement and conditions in the C# Winforms programme

[Anderson]

When pressed on the button, a little bit lower, another button is added and it should only be possible eight times.

Button[] bt = new Button[8];
    private int i { get; set; } = 1;
    private void home_Load(object sender, EventArgs e)
    {
        bt[0] = addButton1;
    }
    public void addButton1_Click(object sender, EventArgs e)
    {
        if (i <= 8)
        {
            Button b = (Button)sender;
            bt[i] = new Button();
        bt[i].BackColor = Color.Transparent;
        bt[i].FlatAppearance.BorderSize = 0;
        bt[i].FlatAppearance.MouseDownBackColor = Color.Transparent;
        bt[i].FlatAppearance.MouseOverBackColor = Color.Transparent;
        bt[i].FlatStyle = FlatStyle.Flat;
        bt[i].ForeColor = Color.White;
        bt[i].Image = Properties.Resources.add;
        bt[i].Location = new Point(543, 132);
        bt[i].Name = "addButton" + i.ToString();
        bt[i].Size = new Size(37, 28);
        bt[i].UseVisualStyleBackColor = false;
        bt[i].Location = new Point(b.Location.X, b.Location.Y + 32);

        Controls.Add(bt[i]);

        bt[i].Click += new EventHandler(addButton1_Click);

        bt[i - 1].Image = Properties.Resources.remove;
        i++;
    }
}

First,I don't quite understand why if there's a condition if (iRO=8), I can still press the last (eighth) button and even get a mistake.

SecondI had a problem, and I didn't actually add buttons. I couldn't figure out what the problem was, and then I fixed it by pumping,:

bt[--i].Image = Properties.Resources.remove;

On:

bt[i - 1].Image = Properties.Resources.remove;

And it all started working.

[Kadir]

I don't know how c#, but in java, the mass index starts with 0♪
size [8] has indices from 0 before 7 (length - 1)

if (i <= 8)  

and here, in checking i for equality, we shall be able to get out of the terrain, the last element we have under index 7.

Try test condition i to 8 if (i < 8)