C# Winform 自适应大小 按上下键切换控件焦点

按上下键切换控件焦点（只对textbox有效）

private void textBox2_KeyDown(object sender, KeyEventArgs e)
        {
if (e.KeyValue == 40 || e.KeyValue == 13)
            {
                SendKeys.Send("{TAB}");
            }
if (e.KeyValue == 38)
            {
int index= this.textBox2.TabIndex;
for (int i = 0; i < this.Controls.Count; i++)
                {
if (this.Controls[i].TabIndex == (index - 1))
                    {
this.Controls[i].Focus();
break;
                    }
                }
            }
        }

自适应大小

private void Form1_SizeChanged(object sender, EventArgs e)
        {
if (this.WindowState.ToString() == "Maximized")
            {
this.dataGridView1.Width = this.Size.Width-35;
            }
else if (this.WindowState.ToString() == "Normal")
            {
this.dataGridView1.Width = this.Size.Width-35;
            }
else
            {
this.dataGridView1.Width = this.Size.Width-35;
            }          
        }