private void numericUpDown1_ValueChanged(object sender, EventArgs e) { trackBar1.Value = (int)numericUpDown1.Value; }

Test4-3

private void vScrollBar1_ValueChanged(object sender, EventArgs e) { this.BackColor = Color.FromArgb(vScrollBar1.Value, vScrollBar2.Value, vScrollBar3.Value); } private void vScrollBar2_ValueChanged(object sender, EventArgs e) { this.BackColor = Color.FromArgb(vScrollBar1.Value, vScrollBar2.Value, vScrollBar3.Value); } private void vScrollBar3_ValueChanged(object sender, EventArgs e) { this.BackColor = Color.FromArgb(vScrollBar1.Value, vScrollBar2.Value, vScrollBar3.Value); }