子窗体加：
public delegate void FrmDAdelegateEventHandler(object sender,EventArgs e);
public event FrmDAdelegateEventHandler FrmDAEvent;

父窗体加：

private void toolStripLabel2_Click(object sender, EventArgs e)
{
if (dGridView1.SelectedCells.Count == 0)
{
MessageBox.Show("请选择要修改的数据！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
else
{
string e_name = dGridView1.SelectedCells[2].Value.ToString();
FrmModifyinfo Minfo = new FrmModifyinfo();
Minfo.e_name = e_name;
Minfo.e_id = dGridView1.SelectedCells[1].Value.ToString();
Minfo.name = name;
Minfo.FrmDAEvent += new FrmModifyinfo.FrmDAdelegateEventHandler(FrmEmployeeDA_Activated);
Minfo.ShowDialog();
}
}