带参数SQL执行DELETE操作

XuguConnection conn = new XuguConnection();
conn.ConnectionString = conn_xugu ;
Try
{
    conn.Open();
    string sql_str = "delete from ta where pid=3";
    XuguCommand cmd = new XuguCommand(sql_str, conn);
    cmd.Connection = conn;

    Int32 ret = cmd.ExecuteNonQuery(); //return effect num 
    return ret;

}
catch (System.Exception ex)
{
    return 0;
}