我正在创建winforms应用程序，用于在我的网络中进行主机监控。我正在ping IP地址，ping的结果显示在listview中（主机IP地址，延迟时间，主机描述）。
当此设备为TIMEOUT时，如何动态更改列表视图中显示的设备颜色？
这是我的主要表格的代码：
public partial class MainFrm : Form
{
private string XmlPath;
private Checker Checker;
private ResourceManager _rm;
OpenFileDialog ofd = new OpenFileDialog();
public MainFrm()
{
InitializeComponent();
_rm = new ResourceManager("HostMonitor.Resources", System.Reflection.Assembly.GetExecutingAssembly());
//assign events to dataset
hosts.Groups.TableNewRow += new DataTableNewRowEventHandler(Groups_TableNewRow);
hosts.Groups.GroupsRowChanged += new HostsData.GroupsRowChangeEventHandler(Groups_GroupsRowChanged);
hosts.Groups.GroupsRowDeleted += new HostsData.GroupsRowChangeEventHandler(Groups_GroupsRowDeleted);
hosts.Hosts.TableNewRow += new DataTableNewRowEventHandler(Hosts_TableNewRow);
hosts.Hosts.HostsRowChanged += new HostsData.HostsRowChangeEventHandler(Hosts_HostsRowChanged);
XmlPath = Path.GetDirectoryName(Path.GetDirectoryName(Application.ExecutablePath));
XmlPath = Path.Combine(Path.GetDirectoryName(XmlPath), "hosts.xml");
XmlPath=Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), "hosts.xml");
hosts.ReadXml(XmlPath);
DataRelation rel = new DataRelation("HostsInGroup", hosts.Groups.Columns["GroupName"], hosts.Hosts.Columns["Group"]);
hosts.Relations.Add(rel);
LoadData();
//start pinging
Checker = new Checker(comps, this);
Checker.Start();
}
void Hosts_HostsRowChanged(object sender, HostsData.HostsRowChangeEvent e)
{
HostsData.HostsRow row = (HostsData.HostsRow)e.Row;
foreach (ListViewItem item in comps.Items)
{
if (item.Tag == row)
{
item.Text = row.HostName;
item.SubItems[2].Text = row.Description;
if ((item.Group == null) || (item.Group.Header != row.Group))
{
foreach (ListViewGroup gr in comps.Groups)
{
if (gr.Header == row.Group)
{
item.Group = gr;
break;
}
}
}
break;
}
}
}
void Hosts_TableNewRow(object sender, DataTableNewRowEventArgs e)
{
HostsData.HostsRow row = (HostsData.HostsRow)e.Row;
ListViewGroup group = null;
if (row.Group!="")
{
foreach (ListViewGroup gr in comps.Groups)
{
if (gr.Header == row.Group)
{
group = gr;
break;
}
}
}
ListViewItem item = new ListViewItem(group);
item.Text = row.HostName;
item.Tag = row;
item.SubItems.Add("");
item.SubItems.Add(row.Description);
comps.Items.Add(item);
}
void Groups_GroupsRowDeleted(object sender, HostsData.GroupsRowChangeEvent e)
{
HostsData.GroupsRow row = (HostsData.GroupsRow)e.Row;
foreach (ListViewGroup gr in comps.Groups)
{
if (gr.Tag == row)
{
comps.Groups.Remove(gr);
return;
}
}
}
void Groups_GroupsRowChanged(object sender, HostsData.GroupsRowChangeEvent e)
{
HostsData.GroupsRow row = (HostsData.GroupsRow)e.Row;
foreach (ListViewGroup gr in comps.Groups)
{
if (gr.Tag == row)
{
gr.Header = row.GroupName;
return;
}
}
}
void Groups_TableNewRow(object sender, DataTableNewRowEventArgs e)
{
ListViewGroup gr = new ListViewGroup();
HostsData.GroupsRow row = (HostsData.GroupsRow)e.Row;
gr.Header = row.GroupName;
gr.Tag = row;
comps.Groups.Add(gr);
}
private void LoadData()
{
comps.Items.Clear();
comps.Groups.Clear();
foreach (HostsData.GroupsRow group in hosts.Groups)
{
ListViewGroup gr = new ListViewGroup();
gr.Header = group.GroupName;
gr.Tag = group;
comps.Groups.Add(gr);
foreach (HostsData.HostsRow host in group.GetChildRows("HostsInGroup"))
{
ListViewItem ht = new ListViewItem(gr);
ht.Text = host.HostName;
ht.SubItems.Add("---");
ht.SubItems.Add(host.Description);
ht.Tag = host;
comps.Items.Add(ht);
}
}
}
这是我班级Checker的代码：
public class Checker
{
private class CheckHostEventArgs:EventArgs
{
private string _hostname;
private ListViewItem _item;
public string HostName
{
get { return _hostname;}
}
public ListViewItem Item
{
get { return _item;}
}
public CheckHostEventArgs(string HostName, ListViewItem item)
{
_hostname=HostName;
_item=item;
}
}
private delegate PingReply CheckHost(CheckHostEventArgs e);
private delegate ListViewItem[] GetCompsDelegate();
private ListView _list;
private MainFrm _frm;
private int AsyncCount = 0;
private Thread _thread;
private ResourceManager _rm;
public Checker(ListView list,MainFrm form)
{
_rm = new ResourceManager("HostMonitor.Resources", System.Reflection.Assembly.GetExecutingAssembly());
_list = list;
_frm = form;
}
public void Start()
{
_thread = new Thread(Main);
_thread.Start();
}
private void Main()
{
try
{
while (true)
{
OneLoop();
Int64 time = Environment.TickCount + Config.Interval;
while (Environment.TickCount < time)
{
Thread.Sleep(100);
}
}
}
catch (ThreadAbortException)
{
return;
}
}
private void OneLoop()
{
foreach (ListViewItem item in GetComps())
{
HostsData.HostsRow host = (HostsData.HostsRow)item.Tag;
//eliminujemy nieaktywne hosty
if (host.HostName == "")
{
continue;
}
if (!host.Active)
{
continue;
}
HostsData.GroupsRow group = (HostsData.GroupsRow)item.Group.Tag;
if (!group.Active)
{
continue;
}
//sprawdzamy aktywne hosty
lock (this)
{
if (AsyncCount < Config.MaxAsyncPings)
{
AsyncCount++;
CheckHost del = new CheckHost(Check);
CheckHostEventArgs e = new CheckHostEventArgs(host.HostName, item);
del.BeginInvoke(e, new AsyncCallback(CheckCallback), item);
}
}
}
}
private PingReply Check(CheckHostEventArgs e)
{
Ping p = new Ping();
try
{
return p.Send(e.HostName, Config.Timeout);
}
catch
{
return null;
}
}
private void CheckCallback(IAsyncResult asResult)
{
if (asResult.IsCompleted)
{
if (_frm.InvokeRequired)
{
AsyncCallback del = new AsyncCallback(CheckCallback);
_frm.Invoke(del, asResult);
}
else
{
try
{
AsyncResult ar = (AsyncResult)asResult;
CheckHost del = (CheckHost)ar.AsyncDelegate;
PingReply r = del.EndInvoke(asResult);
ListViewItem item = (ListViewItem)ar.AsyncState;
if (r != null)
{
switch (r.Status)
{
case IPStatus.Success:
item.SubItems[1].Text = String.Format("{0}", r.RoundtripTime);
break;
default:
item.SubItems[1].Text = r.Status.ToString();
break;
}
}
else
{
item.SubItems[1].Text = _rm.GetString("CheckerErrorOccured");
}
}
catch
{}
lock (this)
{
AsyncCount--;
}
}
}
}
private ListViewItem[] GetComps()
{
if (_frm.InvokeRequired)
{
GetCompsDelegate d = new GetCompsDelegate(GetComps);
return (ListViewItem[])_frm.Invoke(d);
}
else
{
ListViewItem[] result=new ListViewItem[_list.Items.Count];
_list.Items.CopyTo(result, 0);
return result;
}
}
public void Stop()
{
_thread.Abort();
}
}
答案 0 :(得分：0)
使用以下代码更改列表视图中项目的背景颜色：
if (timedout)
listview1.Items[row].BackColor = Color.LightCoral;
else //reset the color
listview1.Items[row].BackColor = listview1.BackColor;
此外，由于您的检查程序运行在与主窗体不同的线程上，因此您必须将此代码放在单独的函数中并使用调用来调用它。