异常提示:调用的目标发生了异常                   foreach (KeyValuePair<string, Dictionary<string, object>> taskItem in taskItems)
                    {
                        ListViewItem li = new ListViewItem();
                        li.SubItems[0].Text = taskItem.Value["ptPrice"].ToString();
                        //li.SubItems.Add(taskItem.Value["ptDuration "].ToString());
                        li.SubItems.Add(taskItem.Value["pName"].ToString());
                        li.SubItems.Add(taskItem.Value["pSN"].ToString());
                        li.SubItems.Add(taskItem.Value["pPrice"].ToString());
                        li.SubItems.Add(taskItem.Value["pEquipment"].ToString());
                        li.SubItems.Add(taskItem.Value["pDuration"].ToString());
                        li.SubItems.Add(taskItem.Value["pgID"].ToString());
                        li.SubItems.Add(taskItem.Value["pCreationDate"].ToString());                        this.listView1.Items.Add(li);
                    }