我遇到了我绝对毫无头绪的最奇怪的错误。我将在此处发布说明以及一些代码，希望你们中的一个可以为我指明正确的方向。
我的应用程序(Winforms)允许用户将项目添加到datagridview(绑定(bind)到列表)，并且每次添加项目时，列表都会序列化为xml文件。最初启动应用程序时，程序将检查xml文件，如果找到该文件，则将先前添加的项目添加到dgv。
Ive还添加了一个DataGridViewButtonColumn来从dgv(列表)中删除项目。这是一些代码。
主类:
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new formFoldingClient());
}
表单的构造函数调用此方法来初始设置dgv
private void InitialDataGridViewSetup()
{
dgvClients.DataSource = null;
//adding delete button column
DataGridViewButtonColumn btnDelete = new DataGridViewButtonColumn();
btnDelete.Name = "btnDelete";
btnDelete.Text = "Delete";
btnDelete.HeaderText = "Delete";
btnDelete.UseColumnTextForButtonValue = true;
btnDelete.DefaultCellStyle.BackColor = Color.DarkBlue;
btnDelete.DefaultCellStyle.ForeColor = Color.White;
dgvClients.Columns.Add(btnDelete);
RefreshDataGridView();
}
每次添加或删除项目时，通过调用以下方法刷新dgv:
private void RefreshDataGridView()
{
dgvClients.DataSource = null;
if (clientList.Count != 0)
{
dgvClients.DataSource = clientList;
dgvClients.Show();
dgvClients.ClearSelection();
}
}
Method that gets triggered when Delete button on a row in the dgv is pressed, followed by the method the performs the delete
private void dgvClients_CellClick(object sender, DataGridViewCellEventArgs e)
{
if (e.ColumnIndex == 0) //delete button has been clicked
{
DeleteClient(dgvClients.Rows[e.RowIndex].Cells[e.ColumnIndex + 1].FormattedValue.ToString());
}
}
private void DeleteClient(string clientToDelete)
{
dgvGrid.DataSource = null;
int removeAt = new int();
for (int i=0; i<clientList.Count; i++)
{
if (clientList[i]._ClientName == clientToDelete)
{
removeAt = i;
break;
}
}
clientList.RemoveAt(removeAt);
LogToFile("Removed client: " + clientToDelete);
LogToBox("Removed client: " + clientToDelete);
RefreshDataGridView();
SaveConfigAsXml();
LogToFile("Changes after deletion persisted to clients.xml.");
}
我相信这是所有必须使用的代码。如果您需要更多，请告诉我。
问题简介
当应用程序首次找到它的XML并将其加载到列表中时，一切都会按预期执行。我可以添加更多项，一次删除所有项，等等。
但是，如果我开始时没有初始xml，则添加项目不是问题。但是，当我删除dgv中最后剩余的项时，在
Main()的最后一行得到了以下异常Index out of range Exception: {"Index -1 does not have a value."}
堆栈跟踪
at System.Windows.Forms.CurrencyManager.get_Item(Int32 index)
at System.Windows.Forms.CurrencyManager.get_Current()
at System.Windows.Forms.DataGridView.DataGridViewDataConnection.OnRowEnter(DataGridViewCellEventArgs e)
at System.Windows.Forms.DataGridView.OnRowEnter(DataGridViewCell& dataGridViewCell, Int32 columnIndex, Int32 rowIndex, Boolean canCreateNewRow, Boolean validationFailureOccurred)
at System.Windows.Forms.DataGridView.SetCurrentCellAddressCore(Int32 columnIndex, Int32 rowIndex, Boolean setAnchorCellAddress, Boolean validateCurrentCell, Boolean throughMouseClick)
at System.Windows.Forms.DataGridView.OnCellMouseDown(HitTestInfo hti, Boolean isShiftDown, Boolean isControlDown)
at System.Windows.Forms.DataGridView.OnCellMouseDown(DataGridViewCellMouseEventArgs e)
at System.Windows.Forms.DataGridView.OnMouseDown(MouseEventArgs e)
at System.Windows.Forms.Control.WmMouseDown(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.DataGridView.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at FoldingMonitorLocalClient.Program.Main() in C:\Users\xbonez\Documents\Visual Studio 2010\Projects\FoldingClient\FoldingClient\Program.cs:line 17
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
更多信息
因此，我刚刚意识到，如果dgv中有n个项目，则仅删除第一个项目也会导致相同的异常。删除项目2至n没问题。
读取xml并将其添加到列表中的代码
private void ReadFromConfigFile()
{
LogToFile("Beginning to read from clients.xml.");
XmlSerializer deserializer = new XmlSerializer(typeof(List<Client>));
try
{
List<Client> tempClientList = new List<Client>();
using (Stream reader = new FileStream("clients.xml", FileMode.Open))
{
tempClientList = ((List<Client>)deserializer.Deserialize(reader));
}
foreach (Client client in tempClientList)
{
clientList.Add(client);
}
}
catch (FileNotFoundException ex)
{
//config file does not exist
this.LogToBox("No saved settings found.");
this.LogToFile("No existing clients.xml present.", ex);
}
catch (Exception ex)
{
LogToBox("Unable to load saved settings. Please see log for more details.");
LogToFile("Failed to read clients.xml.", ex);
}
finally
{
LogToFile("Finished reading clients.xml.");
}
}
单击添加按钮时的代码
private void btnAdd_Click(object sender, EventArgs e)
{
this.tbxClientName.BackColor = Color.White;
this.tbxLogLoc.BackColor = Color.White;
bool exists = false;
foreach (Client client in clientList)
{
if (client._ClientName == this.tbxClientName.Text)
exists = true;
}
if (String.IsNullOrEmpty(tbxClientName.Text))
{
this.tbxClientName.BackColor = Color.Yellow;
LogToBox("Enter Client Name");
LogToFile("user attempted to add client without specifying client name.");
}
else if (String.IsNullOrEmpty(tbxLogLoc.Text))
{
this.tbxLogLoc.BackColor = Color.Yellow;
LogToBox("Select WorkLog location.");
LogToFile("User attempted to add client without specifying worklog location.");
}
else if (exists)
{
//client name entered by user already exists
LogToBox("Client name " + this.tbxClientName.Text + " already exists. Enter another Client name.");
LogToFile("Duplicate client name entered.");
this.tbxClientName.BackColor = Color.Yellow;
}
else
{
//everything is valid. Add new client to list
clientList.Add(new Client(tbxClientName.Text, tbxLogLoc.Text));
LogToBox("Added new client: " + tbxClientName.Text + ".");
LogToFile("Added new client: " + tbxClientName.Text + ".");
this.tbxClientName.Text = String.Empty;
this.tbxLogLoc.Text = String.Empty;
RefreshDataGridView();
SaveConfigAsXml();
}
}
最佳答案
这似乎是.NET中的某种内部绑定(bind)错误。
每当使用绑定(bind)到列表的DataGridView时，我都会遇到完全相同的异常。
我确实花了很多时间试图找到解决方案，今天终于设法摆脱了这些异常(exception)情况-将ICurrencyManagerProvider接口(interface)添加到我的所有列表中。
该接口(interface)仅具有“CurrencyManager”只读属性和“GetRelatedCurrencyManager”方法。
我只是在两者中都返回Nothing，仅此而已，不再是CurrencyManager中“索引-1没有值”的东西。
关于c# - 索引1没有值，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/4965963/