Form1主窗体：

复制代码 代码如下:
public delegate void SetVisiableHandler();//定义委托类型

private void button1_Click(object sender,EventArgs e)//单击事件，打开子窗体
{
Form2 frm = new Form2(new SetVisiableHandler(SetVisiable));
frm.Show();
}

private void SetVisiable()
{
dataGridView1.Rows.Add("123","456","789");
}

Form2子窗体：

复制代码 代码如下:
private SetVisiableHandler m_setVisable;//声明委托变量
public Form2(SetVisiableHandler setvisiable)
{
InitializeComponent();
this.m_setVisiable = setvisiable;
}

public void butten1_Click(object sender,EventArgs e)
{
if(this.m_setVisiable != null)
{
this.m_setVisiable();
}
}