我在datagrid下面放了一个删除按纽,当我选中哪个我就让它删除哪个,怎么实现呀

我这样写为什么只删除一个呢
private void Button2_Click(object sender, System.EventArgs e)
{
try
{
conn=new SqlConnection(ConfigurationSettings.AppSettings["sqlConn"]);
string myid="";
for(int i=0;i<DataGrid1.Items.Count;i++)
{
CheckBox cb=(CheckBox)this.DataGrid1.Items[i].FindControl("ck");
if(cb.Checked==true)
{
myid=this.DataGrid1.DataKeys[i].ToString();
string sql="delete SD_AddAnnouce where id="+myid.ToString();
conn.Open();
SqlCommand comm=new SqlCommand(sql,conn);
comm.ExecuteNonQuery();
Response.Write("<script>alert('删除公告成功！')</script>");
conn.Close();
dgbind();
}
}
}
catch(Exception err)
{
Response.Write(err.ToString());
}
}

好了,我改好了!这样就行了!
try
{
conn=new SqlConnection(ConfigurationSettings.AppSettings["sqlConn"]);
string myid="";
for(int i=0;i<DataGrid1.Items.Count;i++)
{
CheckBox cb=(CheckBox)this.DataGrid1.Items[i].FindControl("ck");
if(cb.Checked==true)
{
myid+=DataGrid1.DataKeys[i].ToString() +",";


}
}
myid=myid.Substring(0,myid.Length-1);
string sql="delete SD_AddAnnouce where id in ("+myid.ToString() + ")";
conn.Open();
SqlCommand comm=new SqlCommand(sql,conn);
comm.ExecuteNonQuery();
Response.Write("<script>alert('删除公告成功！')</script>");
conn.Close();
dgbind();
}
catch(Exception err)
{
Response.Write(err.ToString());
}

郁闷!怎么删除不了呢,它也不包错呀

就是我把最后一页的数据全选了之后,进行删除,就删除不了,而且还没有包错

打印出来是这个delete SD_AddAnnouce where id in (449,450,451,452,453,454)

好了,能删除了,原来我把数据库的表明写错了!呵呵!谢谢斑竹!!!