我需要能够从列表框中删除项目但是当我按下删除功能并说“是”时我想要删除我得到此异常：Items collection cannot be modified when the DataSource property is set.
现在我想知道如何处理这件事。
namespace Flashloader
{
public partial class Form1 : Form
{
private controllerinifile _controllerIniFile;
private toepassinginifile _toepassingIniFile;
// private Toepassinglist _toepassingList;
private StringList _comPorts;
public Form1()
{
InitializeComponent();
backgroundWorker1.WorkerReportsProgress = true;
backgroundWorker1.WorkerSupportsCancellation = true;
button4.Visible = false;
_controllerIniFile = new controllerinifile();
_toepassingIniFile = new toepassinginifile(_controllerIniFile.Controllers);
// _toepassingList = new Toepassinglist(_controllerList).FromIniFile();
_comPorts = new StringList();
_applicationListBox.DataSource = _toepassingIniFile.ToePassingen;
_controllercombobox.DataSource = _controllerIniFile.Controllers;
_applicationListBox.Refresh();
_controllercombobox.Refresh();
Settings settings = _toepassingIniFile.Settings;
textBox3.Text = settings.Port;
textBox4.Text = settings.Baudrate;
}
// File select Button and file directory
private void button2_Click(object sender, EventArgs e)
{
appfile.Filter = "Srec Files (.a20; .a21; .a26; .a44)|*.a20; *.a21; *.a26; *.a44|All files (*.*)|*.*";
{
if (appfile.ShowDialog() == DialogResult.OK)
{
System.IO.StreamReader sr = new
System.IO.StreamReader(appfile.FileName);
sr.Close();
}
}
String filedata = appfile.FileName;
appfile.Title = ("Choose a file");
appfile.InitialDirectory = System.IO.Path.Combine(System.IO.Path.GetDirectoryName(Application.ExecutablePath), @"C:\\\\Projects\\flashloader2013\\mainapplication\\");
textBox1.Text = string.Format("{0}", appfile.FileName);
}
// textbox for the bootfile
private void textBox2_TextChanged(object sender, EventArgs e)
{
}
// start button for sending appfiles
private void button1_Click(object sender, EventArgs e)
{
backgroundWorker1.RunWorkerAsync();
serialPort1.Open();
if (MessageBox.Show(appfile.FileName + " is selected and ready to be send,Are you sure you want to send the selected file?", "", MessageBoxButtons.YesNo) == DialogResult.No)
{
MessageBox.Show("The selected file will not be send.", "", MessageBoxButtons.OK);
}
else
{
button1.Visible = false;
button4.Visible = true;
}
try
{
using (FileStream inputstream = new FileStream(OpenBoot.FileName, FileMode.Open, FileAccess.Read, FileShare.Read, 32 * 1024 * 1024, FileOptions.SequentialScan))
{
byte[] buffer = new byte[8 * 1024 * 1024];
long bytesRead = 0, streamLength = inputstream.Length;
inputstream.Position = 0;
while (bytesRead < streamLength)
{
long toRead = streamLength - bytesRead;
if (toRead < buffer.Length)
buffer = new byte[(int)toRead];
if (inputstream.Read(buffer, 0, buffer.Length) != buffer.Length)
throw new Exception("File read error");
bytesRead += buffer.Length;
serialPort1.Write(buffer, 0, buffer.Length);
}
}
}
catch
{
MessageBox.Show("No file selected");
}
StringList list = new StringList().FromFile(appfile.FileName);
// Read file and put it in a list that will be sorted.
foreach (String line in list)
{
list.Sort();
serialPort1.Write(line);
}
MessageBox.Show("Bootfile and Applicationfile are send succesfully.");
}
// abort button for sending files
private void button4_Click(object sender, EventArgs e)
{
backgroundWorker1.CancelAsync();
button4.Visible = false;
button1.Visible = true;
progressBar1.Value = 0;
timer1.Enabled = false;
serialPort1.Close();
}
// backgroundworkers
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
DateTime start = DateTime.Now;
e.Result = "";
for (int i = 0; i < 100; i++)
{
System.Threading.Thread.Sleep(50);
backgroundWorker1.ReportProgress(i, DateTime.Now);
if (backgroundWorker1.CancellationPending)
{
e.Cancel = true;
return;
}
}
TimeSpan duration = DateTime.Now - start;
e.Result = "Duration: " + duration.TotalMilliseconds.ToString() + " ms.";
}
private void backgroundWorker1_ProgressChanged(object sender,
ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
DateTime time = Convert.ToDateTime(e.UserState);
}
private void backgroundWorker1_RunWorkerCompleted(object sender,
RunWorkerCompletedEventArgs e)
{
if (e.Cancelled)
{
MessageBox.Show("The task has been cancelled");
}
else if (e.Error != null)
{
MessageBox.Show("Error. Details: " + (e.Error as Exception).ToString());
}
else
{
MessageBox.Show("The task has been completed. Results: " + e.Result.ToString());
}
}
private void Boot_button_Click(object sender, EventArgs e)
{
OpenBoot.Filter = "Binary Files (.BIN; .md6; .md7)|*.BIN; *.md6; *.md7|All Files (*.*)|*.*";
{
if (OpenBoot.ShowDialog() == DialogResult.OK)
{
System.IO.StreamReader sr = new
System.IO.StreamReader(appfile.FileName);
sr.Close();
}
}
String filedata = OpenBoot.FileName;
OpenBoot.Title = ("Choose a file");
OpenBoot.InitialDirectory = "C:\\Projects\\flashloader2013\\mainapplication\\Bootfiles";
textBox2.Text = string.Format("{0}", OpenBoot.FileName);
}
// Saving the settings to the INI file.
private void SaveSettings()
{
Toepassing toepassing = GetCurrentApplication();
if (toepassing == null)
{
MessageBox.Show("No Application selected");
return;
}
toepassing.Controller = (Controller)_controllercombobox.SelectedItem;
toepassing.Lastfile = textBox1.Text;
// toepassing.TabTip =
_toepassingIniFile.Save();
}
private Controller GetCurrentController()
{
int index = _controllercombobox.SelectedIndex;
if (index < 0)
return null;
return _controllerIniFile.Controllers[index];
}
private Toepassing GetCurrentApplication()
{
int index = _applicationListBox.SelectedIndex;
if (index < 0)
return null;
return _toepassingIniFile.ToePassingen[index];
}
private void typelistbox_SelectedIndexChanged(object sender, EventArgs e)
{
Toepassing toepassing = GetCurrentApplication();
if (toepassing == null)
{
// TODO velden leegmaken
}
else
{
// appfile.InitialDirectory = Path.GetDirectoryName(controller.Lastfile);
appfile.FileName = toepassing.Lastfile;
textBox1.Text = toepassing.Lastfile;
_controllercombobox.SelectedItem = toepassing.Controller;
}
}
private void _controllercombobox_SelectedIndexChanged(object sender, EventArgs e)
{
Controller controller = GetCurrentController();
if (controller == null)
{
// TODO velden leegmaken
}
else
{
textBox2.Text = controller.Bootfile;
}
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
this.Close();
}
private void changeCurrentControllerToolStripMenuItem_Click(object sender, EventArgs e)
{
var controlleredit = new Controlleredit(_controllerIniFile);
controlleredit.Show();
Refresh();
}
private void addControllerToolStripMenuItem_Click(object sender, EventArgs e)
{
var controllersettings = new Newcontroller(_controllerIniFile);
controllersettings.ShowDialog();
_controllercombobox.DataSource = null;
_controllercombobox.DataSource = _controllerIniFile.Controllers;
// Refresh();
// _controllercombobox.Refresh();
}
private void newapplicationBtton_Click(object sender, EventArgs e)
{
var newapplication = new NewApplication(_toepassingIniFile);
newapplication.ShowDialog();
_applicationListBox.DataSource = null;
_applicationListBox.DataSource = _toepassingIniFile.ToePassingen;
}
/////////////////////////////错误在这里///////////// ////////////////
private void button3_Click(object sender, EventArgs e)
{
if (MessageBox.Show("You are about to delete application: "+ Environment.NewLine + _applicationListBox.SelectedItem +Environment.NewLine + " Are you sure you want to delete the application?", "", MessageBoxButtons.YesNo) == DialogResult.No)
{
MessageBox.Show("The application will not be deleted.", "", MessageBoxButtons.OK);
}
else if (this._applicationListBox.SelectedIndex >= 0)
this._applicationListBox.Items.RemoveAt(this._applicationListBox.SelectedIndex);
}
}
}
答案 0 :(得分：2)
错误说得非常清楚：您必须从基础数据源中删除该项，您无法手动删除它。如果要手动删除/添加项目，则不应使用数据绑定，而是手动构建列表。
答案 1 :(得分：0)
尝试从数据源中删除，如下所示：
string myobj = this._applicationListBox.SelectedValue.ToString();
data.Remove(myobj );
_applicationListBox.DataSource = null;
_applicationListBox.DataSource = data;
答案 2 :(得分：0)
例外情况说，您无法直接从ListBox删除项目 - 您必须将其从基础DataSource中删除，然后重新绑定控件（如果它未绑定到BindingSource，例如）
private void button3_Click(object sender, EventArgs e)
{
if (MessageBox.Show("You are about to delete application: "+ Environment.NewLine + _applicationListBox.SelectedItem +Environment.NewLine + " Are you sure you want to delete the application?", "", MessageBoxButtons.YesNo) == DialogResult.No)
{
MessageBox.Show("The application will not be deleted.", "", MessageBoxButtons.OK);
}
else if (this._applicationListBox.SelectedIndex >= 0)
{
var item = this.GetCurrentApplication();
_toepassingIniFile.ToePassingen.Remove(item);
_applicationListBox.DataSource = null;
_applicationListBox.DataSource = _toepassingIniFile.ToePassingen;
}
}
你的代码很难阅读，所以我有点猜测类等，但它应该可以工作。
答案 3 :(得分：0)
正如其他人所说。您必须具有绑定到列表框的列表。您无法直接从列表框中删除。
您应该从列表中删除
private Toepassinglist _toepassingList
这是列表框的数据源。 删除你想要的项目......
this._toepassingList.Items.RemoveAt(this._applicationListBox.SelectedIndex);
答案 4 :(得分：0)
您可以从列表中删除：---
<强> ListName.Items.RemoveAt（现在的位置）;