如何获取DataSet的当前状态,如Delphi中的State[dsInsert,dsBrowse..]

Question

chenJDataSet.pub_jiaoyuju.newrow()后,
执行以下语句会提示"pub_jiaoyujuBindingSource.Position"不存在.所以想在不是"插入","删除"状态下执行以下代码
            if (comboBox1.SelectedValue != null)
                comboBox1.SelectedValue = chenJDataSet.pub_jiaoyuju.Rows[pub_jiaoyujuBindingSource.Position]["parentid"];

Answer 1

看看 chenJDataSet 是否榜定了
看看 pub_jiaoyujuBindingSource.Position 是 -1 不如果是 -1
证明 没榜定好，或没榜定上
newrow() 后 add 回去没？还是把完整的代码贴出来吧

Answer 2

Dataset1.Tables[0].Rows[0].RowState而且 chenJDataSet.pub_jiaoyuju.Add(chenJDataSet.pub_jiaoyuju.newrow())

Answer 3

在vs2005环境中,chenJDataSet 已绑定,
单击"bindingNavigatorAddNewItem"时执行pub_jiaoyujuBindingSource的AddNew()方法,在pub_jiaoyujuBindingSource_PositionChanged的事件中出错,主要是提示在"pub_jiaoyujuBindingSource.Position"没有任何行!如何解决? private void bindingNavigatorAddNewItem_Click(object sender, EventArgs e)
        {
            this.pub_jiaoyujuBindingSource.AddNew();添加新行
        }       private void pub_jiaoyujuBindingSource_PositionChanged(object sender, EventArgs e)
        {            if (comboBox1.SelectedValue != null)
                comboBox1.SelectedValue = chenJDataSet.pub_jiaoyuju.Rows[pub_jiaoyujuBindingSource.Position]["parentid"];
        }

Answer 4

//获取不同版本的DataRow
using System;
using System.IO;
using System.Text;
using System.Diagnostics;
using System.Threading;
using System.Collections;
using System.Data;
using System.Xml;
using System.Management;
using System.Net;
namespace Zhzuo
{
class ZZConsole
{
[STAThread]
static void Main(string[] args)
{
DataSet ds = new DataSet();
CreatDataSetSchema(ds);
InitData(ds);
DataRow drdel = ds.Tables["Hosts"].Rows[0];
drdel.Delete();
Console.WriteLine(drdel.HasVersion(DataRowVersion.Default).ToString());
foreach(DataRow dr in ds.Tables["Hosts"].GetChanges(DataRowState.Deleted).Rows)
{
//if(dr.HasVersion(DataRowVersion.Current))
//{
Console.WriteLine((string)dr["HId"]);
Console.WriteLine(dr["IsLocal",DataRowVersion.Original].ToString());
//}
}
Console.WriteLine("end");
Console.ReadLine();
}
//初始化数据集结构
private static void CreatDataSetSchema(DataSet ds)
{
DataTable dt = new DataTable("Hosts");
DataColumn dc = new DataColumn("HId",typeof(String));
dt.Columns.Add(dc);
dc = new DataColumn("IsLocal",typeof(Boolean));
dt.Columns.Add(dc);
ds.Tables.Add(dt);
}
//加入数据
private static void InitData(DataSet ds)
{
DataRow hostsRow = ds.Tables["Hosts"].NewRow();
hostsRow["HId"] = "192.192.132.229";
hostsRow["IsLocal"] = true;
ds.Tables["Hosts"].Rows.Add(hostsRow); hostsRow = ds.Tables["Hosts"].NewRow();
hostsRow["HId"] = "192.192.132.231";
hostsRow["IsLocal"] = false;
ds.Tables["Hosts"].Rows.Add(hostsRow); hostsRow = ds.Tables["Hosts"].NewRow();
hostsRow["HId"] = "192.192.132.233";
hostsRow["IsLocal"] = false;
ds.Tables["Hosts"].Rows.Add(hostsRow);
}
}

}