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Why I cannot delete properly from a List and ListView?

I have a ListView in my Form.
I want to delete a row, but when I select one and delete it, later it comes back and I can't delete from the List where data comes from.
Why is that?
Pontszam pt = new Pontszam();
List<int> pontszamook = new List<int>();
List<string> nevek = new List<string>();
List<string> idk = new List<string>();
List<string> ptList = new List<string>();
int osszSor = 0;
public int sorokSzama()
{
osszSor = pt.select().Count;
return osszSor;
}
private void Ponttablazat_Load(object sender, EventArgs e)
{
osszSor = sorokSzama();
ptList = pt.select();
listScore.Items.Clear();
for (int i = 0; i < osszSor; i++)
{
string[] adatok = ptList[i].Split(';');
idk.Add(adatok[0]);
nevek.Add(adatok[1]);
pontszamook.Add(Convert.ToInt32(adatok[2]));
var row = new string[] { nevek[i], Convert.ToString(pontszamook[i]) };
ListViewItem lvi = new ListViewItem(idk[i]);
lvi.SubItems.AddRange(row);
listScore.Items.Add(lvi);
}
}
private void btnDelete_Click(object sender, EventArgs e)
{
if (listScore.SelectedItems != null)
{
for (int i = listScore.SelectedItems.Count - 1; i >= 0; i--)
{
ListViewItem itm = listScore.SelectedItems[i];
int indeX = itm.Index;
listScore.Items[itm.Index].Remove();
ptList[indeX] = null;
idk[indeX] = null;
nevek[indeX] = null;
pontszamook[indeX] = -1;
pt.deletetRow(itm.Index);
}
}
}
private void btnDelete_Click(object sender, EventArgs e) { if (listScore.SelectedItems != null) { for (int i = listScore.SelectedItems.Count - 1; i >= 0; i--) { ListViewItem itm = listScore.SelectedItems[i]; int indeX = itm.Index; listScore.Items[itm.Index].Remove(); ptList[indeX] = null; idk[indeX] = null; nevek[indeX] = null; pontszamook[indeX] = -1; pt.deletetRow(itm.Index); } } }

Winforms insert image into ListView / ImageList at index

Winforms, C#, VS2017
ImageList does not have an Insert method (however ListViewItemCollection does). I have tried a few different ways to insert a new image into the middle of a ListView and it's LargeImageList, but not getting it to work quite properly.
Anyone have any tried and true code that works properly?
This is what I have, but the images don't get synced properly to the items in the list.
protected void InsertThumbnail(string key, string keySelected)
{
var newImageList = new ImageList()
{
ImageSize = new Size(thumbWidth, thumbHeight)
};
var itemNew = new ListViewItem();
var foundSelected = false;
//lvAllPages.BeginUpdate();
for (int i = 0; i < lvAllPages.Items.Count; i++)
{
var item = lvAllPages.Items[i];
newImageList.Images.Add(item.Tag.ToString(), lvAllPages.LargeImageList.Images[i]);
if (item.Tag.ToString() == keySelected)
{
var image = batch.GetThumbnail(key);
newImageList.Images.Add(key, image);
itemNew = new ListViewItem()
{
BackColor = Color.Aquamarine,
ImageIndex = i,
Tag = key,
};
if (isLocal)
itemNew.Text = $"{GetFileName(key)} (insert) - {itemNew.ImageIndex}";
foundSelected = true;
}
if (foundSelected)
{
item.ImageIndex = item.ImageIndex + 1;
if (isLocal)
item.Text = $"{GetFileName(item.Tag.ToString())} - {item.ImageIndex}";
}
}
lvAllPages.LargeImageList.Dispose();
lvAllPages.LargeImageList = newImageList;
lvAllPages.Items.Insert(itemNew.ImageIndex, itemNew);
}
One more related thing, but not pertinent to the problems I am having. For anyone looking at this question and having similar issues, this helped with the issue of sorting items after inserting a new one. Default behavior when you insert a new ListViewItem at a given index, it will appear at the bottom of the list. I found this handy class to keep items sorted by index, which solved that problem:
class CompareByIndex : IComparer
{
private readonly ListView _listView;
public CompareByIndex(ListView listView)
{
this._listView = listView;
}
public int Compare(object x, object y)
{
int i = this._listView.Items.IndexOf((ListViewItem)x);
int j = this._listView.Items.IndexOf((ListViewItem)y);
return i - j;
}
}
And in the form load:
lvAllPages.ListViewItemSorter = new CompareByIndex(lvAllPages);

Obviously, that's a design decision. ImageList.Images is a ImageCollection and as such, it implements the IList interface.
Unfortunately, the Insert() method is allowed to throw a NotSupportedException. And that's what the list will do when used like a IList:
((IList)imageList.Images).Insert(5, new Bitmap(10,10));
System.NotSupportedException: 'Specified method is not supported.'
In order to have the images shown in a specific order, use the Add() method which takes the key:
imageList.Images.Add("1", new Bitmap(100,100));
That should also enable you to replace the image:
imageList.Images.RemoveByKey("1");
imageList.Images.Add("1", new Bitmap(200,200));
For that to work, you need to set the Sorting property:
listView1.Sorting = SortOrder.Ascending;
For storing additional information like path etc. use anotther data structure with the same key.
Here's the code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
ImageList imageList = new ImageList();
Dictionary<string, Metadata> metadata = new Dictionary<string, Metadata>();
private string dir = #"H:\temp";
private void button1_Click(object sender, EventArgs e)
{
// You would set this in the designer, probably
listView1.Sorting = SortOrder.Ascending;
listView1.View = View.LargeIcon;
listView1.LargeImageList = imageList;
// Make sure we start from the beginning
listView1.Items.Clear();
imageList.Images.Clear();
metadata.Clear();
// Add items
for (int i = 0; i < 10; i++)
{
var filename = "1 ("+(i+1)+").png"; // Just strange names I have
var fullFileName = Path.Combine(dir, filename);
imageList.Images.Add(i.ToString(), Bitmap.FromFile(fullFileName));
metadata.Add(i.ToString(), new Metadata{Path = fullFileName});
listView1.Items.Add(i.ToString(), "Image " + i, i.ToString());
}
// Update view
listView1.Refresh();
listView1.Invalidate();
}
private void button2_Click(object sender, EventArgs e)
{
for (int i = 3; i < 6; i++)
{
var filename = "1 ("+(i+2)+").png";
var fullFileName = Path.Combine(dir, filename);
// Change image
imageList.Images.RemoveByKey(i.ToString());
imageList.Images.Add(i.ToString(), Bitmap.FromFile(fullFileName));
// Match metadata and image
metadata[i.ToString()] = new Metadata{Path = fullFileName};
}
listView1.Refresh();
}
private void listView1_SelectedIndexChanged(object sender, EventArgs e)
{
if (listView1.SelectedItems.Count > 0)
{
var key = listView1.SelectedItems[0].ImageKey;
label1.Text = metadata[key].Path;
}
else
{
label1.Text = "No image selected";
}
}
}
internal class Metadata
{
internal string Path;
}

Dynamically add a checkbox column

I'm trying to create a column programmatically and set it as checkbox.
I'm doing it on Expanded event.
The snippet of my code is
if (qtdColumns < qtdPermissions)
{
for (int i = qtdColumns; i < qtdPermissions; i++)
{
OLVColumn aNewColumn = new OLVColumn();
aNewColumn.Text = string.Empty;
aNewColumn.AspectGetter += delegate (object x)
{
if (((Model)x).permissions.Count() > 0)
{
aNewColumn.CheckBoxes = true;
return permission.Label;
}
else
{
aNewColumn.CheckBoxes = false;
return "";
}
};
this.MyTreeListView.AllColumns.Add(aNewColumn);
qtdColumns++;
}
}
But the only result I get is like this:

CheckBoxList In GridView Only Remember The First Option Ticked When New Row Added

I have a grid view with multiple columns which allow user to fill in the data and they are able to add a new row after finishing filling the data. Among the columns, there is a column with CheckBoxList which I allow user to multiple select the option on the CheckBoxList but every time add a new row, only the first option select by the user is remain while other selection is gone. How am I able to let the option selected by the user remain while I add a new row?
private void SetPreviousDataLecturer()
{
int rowIndex = 0;
if (ViewState["LecturerGridView"] != null)
{
DataTable dataTableCurrent = (DataTable)ViewState["LecturerGridView"];
if (dataTableCurrent.Rows.Count > 0)
{
for (int i = 0; i < dataTableCurrent.Rows.Count; i++)
{
TextBox textBoxLName = (TextBox)LecturerGridView.Rows[rowIndex].Cells[1].FindControl("LecturerName");
TextBox textBoxLID = (TextBox)LecturerGridView.Rows[rowIndex].Cells[2].FindControl("LecturerID");
TextBox textBoxLAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[3].FindControl("LecturerAddress");
TextBox textBoxLPNumber = (TextBox)LecturerGridView.Rows[rowIndex].Cells[4].FindControl("LecturerPNumber");
TextBox textBoxLEAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[5].FindControl("LecturerEAddress");
CheckBoxList checkBoxListLCourse = (CheckBoxList)LecturerGridView.Rows[rowIndex].Cells[6].FindControl("LecturerCourse");
TextBox textBoxLPassword = (TextBox)LecturerGridView.Rows[rowIndex].Cells[7].FindControl("LecturerPassword");
LecturerGridView.Rows[i].Cells[0].Text = Convert.ToString(i + 1);
textBoxLName.Text = dataTableCurrent.Rows[i]["LecturerName"].ToString();
textBoxLID.Text = dataTableCurrent.Rows[i]["LecturerID"].ToString();
textBoxLAdd.Text = dataTableCurrent.Rows[i]["LecturerAddress"].ToString();
textBoxLPNumber.Text = dataTableCurrent.Rows[i]["LecturerPNumber"].ToString();
textBoxLEAdd.Text = dataTableCurrent.Rows[i]["LecturerEAddress"].ToString();
checkBoxListLCourse.SelectedValue = dataTableCurrent.Rows[i]["LecturerCourse"].ToString();
textBoxLPassword.Text = dataTableCurrent.Rows[i]["LecturerPassword"].ToString();
rowIndex++;
}
}
}
}
private void AddNewRowToLecturerGV()
{
int rowIndex = 0;
if (ViewState["LecturerGridView"] != null)
{
DataTable dataTableCurrent = (DataTable)ViewState["LecturerGridView"];
DataRow dataRowCurrent = null;
if (dataTableCurrent.Rows.Count > 0)
{
for (int i = 1; i <= dataTableCurrent.Rows.Count; i++)
{
TextBox textBoxLName = (TextBox)LecturerGridView.Rows[rowIndex].Cells[1].FindControl("LecturerName");
TextBox textBoxLID = (TextBox)LecturerGridView.Rows[rowIndex].Cells[2].FindControl("LecturerID");
TextBox textBoxLAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[3].FindControl("LecturerAddress");
TextBox textBoxLPNumber = (TextBox)LecturerGridView.Rows[rowIndex].Cells[4].FindControl("LecturerPNumber");
TextBox textBoxLEAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[5].FindControl("LecturerEAddress");
CheckBoxList checkBoxListLCourse = (CheckBoxList)LecturerGridView.Rows[rowIndex].Cells[6].FindControl("LecturerCourse");
TextBox textBoxLPassword = (TextBox)LecturerGridView.Rows[rowIndex].Cells[7].FindControl("LecturerPassword");
dataRowCurrent = dataTableCurrent.NewRow();
dataRowCurrent["RowNumber"] = i + 1;
dataTableCurrent.Rows[i - 1]["LecturerName"] = textBoxLName.Text;
dataTableCurrent.Rows[i - 1]["LecturerID"] = textBoxLID.Text;
dataTableCurrent.Rows[i - 1]["LecturerAddress"] = textBoxLAdd.Text;
dataTableCurrent.Rows[i - 1]["LecturerPNumber"] = textBoxLPNumber.Text;
dataTableCurrent.Rows[i - 1]["LecturerEAddress"] = textBoxLEAdd.Text;
dataTableCurrent.Rows[i - 1]["LecturerCourse"] = checkBoxListLCourse.SelectedValue.ToString();
dataTableCurrent.Rows[i - 1]["LecturerPassword"] = textBoxLPassword.Text;
rowIndex++;
}
dataTableCurrent.Rows.Add(dataRowCurrent);
ViewState["LecturerGridView"] = dataTableCurrent;
LecturerGridView.DataSource = dataTableCurrent;
LecturerGridView.DataBind();
}
}
else
{
Response.Write("ViewState is null.");
}
SetPreviousDataLecturer();
}

You need to maintain state for selected checkbox. On the button click 'Add new row' first get the state of each rows in a DataTable and add a blank row then populate that DataTable.
You need to maintain checkbox's selected item's state also. You can get selected values in a CSV as :
string selectedItems = String.Join(",",
checkBoxListLCourse.Items.OfType<ListItem>().Where(r => r.Selected)
.Select(r => r.Value));
and you can restore as :
string[] items = selectedItems.Split(',');
for (int i = 0; i < checkBoxListLCourse.Items.Count; i++)
{
if (items.Contains(checkBoxListLCourse.Items[i].Value))
{
checkBoxListLCourse.Items[i].Selected = true;
}
}

My answer. This answer has some problem like the checkbox list will automatically scroll to the most top when we tick on anything in the checkbox list.
private void SetPreviousDataLecturer()
{
int rowIndex = 0;
if (ViewState["LecturerGridView"] != null)
{
DataTable dataTableCurrent = (DataTable)ViewState["LecturerGridView"];
if (dataTableCurrent.Rows.Count > 0)
{
for (int i = 0; i < dataTableCurrent.Rows.Count; i++)
{
TextBox textBoxLName = (TextBox)LecturerGridView.Rows[rowIndex].Cells[1].FindControl("LecturerName");
TextBox textBoxLID = (TextBox)LecturerGridView.Rows[rowIndex].Cells[2].FindControl("LecturerID");
TextBox textBoxLAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[3].FindControl("LecturerAddress");
TextBox textBoxLPNumber = (TextBox)LecturerGridView.Rows[rowIndex].Cells[4].FindControl("LecturerPNumber");
TextBox textBoxLEAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[5].FindControl("LecturerEAddress");
CheckBoxList checkBoxListLCourse = (CheckBoxList)LecturerGridView.Rows[rowIndex].Cells[6].FindControl("LecturerCourse");
TextBox textBoxLPassword = (TextBox)LecturerGridView.Rows[rowIndex].Cells[7].FindControl("LecturerPassword");
LecturerGridView.Rows[i].Cells[0].Text = Convert.ToString(i + 1);
textBoxLName.Text = dataTableCurrent.Rows[i]["LecturerName"].ToString();
textBoxLID.Text = dataTableCurrent.Rows[i]["LecturerID"].ToString();
textBoxLAdd.Text = dataTableCurrent.Rows[i]["LecturerAddress"].ToString();
textBoxLPNumber.Text = dataTableCurrent.Rows[i]["LecturerPNumber"].ToString();
textBoxLEAdd.Text = dataTableCurrent.Rows[i]["LecturerEAddress"].ToString();
checkBoxListLCourse.Text = dataTableCurrent.Rows[i]["LecturerCourse"].ToString();
string lecturerCourse = dataTableCurrent.Rows[i]["LecturerCourse"].ToString();
if (!string.IsNullOrEmpty(lecturerCourse))
{
for (int j = 0; j < lecturerCourse.Split(',').Length; j++)
{
checkBoxListLCourse.Items.FindByValue(lecturerCourse.Split(',')[j].ToString()).Selected = true;
}
}
textBoxLPassword.Text = dataTableCurrent.Rows[i]["LecturerPassword"].ToString();
rowIndex++;
}
}
}
}
private void AddNewRowToLecturerGV()
{
int rowIndex = 0;
if (ViewState["LecturerGridView"] != null)
{
DataTable dataTableCurrent = (DataTable)ViewState["LecturerGridView"];
DataRow dataRowCurrent = null;
if (dataTableCurrent.Rows.Count > 0)
{
for (int i = 1; i <= dataTableCurrent.Rows.Count; i++)
{
TextBox textBoxLName = (TextBox)LecturerGridView.Rows[rowIndex].Cells[1].FindControl("LecturerName");
TextBox textBoxLID = (TextBox)LecturerGridView.Rows[rowIndex].Cells[2].FindControl("LecturerID");
TextBox textBoxLAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[3].FindControl("LecturerAddress");
TextBox textBoxLPNumber = (TextBox)LecturerGridView.Rows[rowIndex].Cells[4].FindControl("LecturerPNumber");
TextBox textBoxLEAdd = (TextBox)LecturerGridView.Rows[rowIndex].Cells[5].FindControl("LecturerEAddress");
CheckBoxList checkBoxListLCourse = (CheckBoxList)LecturerGridView.Rows[rowIndex].Cells[6].FindControl("LecturerCourse");
TextBox textBoxLPassword = (TextBox)LecturerGridView.Rows[rowIndex].Cells[7].FindControl("LecturerPassword");
dataRowCurrent = dataTableCurrent.NewRow();
dataRowCurrent["RowNumber"] = i + 1;
dataTableCurrent.Rows[i - 1]["LecturerName"] = textBoxLName.Text;
dataTableCurrent.Rows[i - 1]["LecturerID"] = textBoxLID.Text;
dataTableCurrent.Rows[i - 1]["LecturerAddress"] = textBoxLAdd.Text;
dataTableCurrent.Rows[i - 1]["LecturerPNumber"] = textBoxLPNumber.Text;
dataTableCurrent.Rows[i - 1]["LecturerEAddress"] = textBoxLEAdd.Text;
string lecturerCourse = string.Empty;
foreach (ListItem item in checkBoxListLCourse.Items)
{
if (item.Selected)
{
if (!string.IsNullOrEmpty(lecturerCourse))
{
lecturerCourse += ",";
}
lecturerCourse += item.Value;
}
}
dataTableCurrent.Rows[i - 1]["LecturerCourse"] = lecturerCourse;
dataTableCurrent.Rows[i - 1]["LecturerPassword"] = textBoxLPassword.Text;
rowIndex++;
}
dataTableCurrent.Rows.Add(dataRowCurrent);
ViewState["LecturerGridView"] = dataTableCurrent;
LecturerGridView.DataSource = dataTableCurrent;
LecturerGridView.DataBind();
}
}
else
{
Response.Write("ViewState is null.");
}
SetPreviousDataLecturer();
}

How to store name of dynamic checkbox in an String array

How can store name of dynamically created checkbox in a String array when I don't know how many checkbox will user select at runtime.
Say I have 10 dynamic checkboxes and out of 10 user select 6 checkboxes randomly now how can get the name of those selected checkboxes and store them in a String array.
I know how to use event handler on dynamic check box but confused how to declare Straing array when I don't know what will be be size of an array.
Here what I have done till now -
private void CheckBoxCheckedChanged(object sender, EventArgs e)
{
CheckBox c = (CheckBox)sender;
//Label myLabel;
String str = null;
if (c.Checked == true)
{
str = c.Text;
gpBox[gpcount] = new GroupBox();
gpBox[gpcount].Name = "gpBox" + Convert.ToString(count);
gpBox[gpcount].Text = str;
gpBox[gpcount].Location = new Point(5, gpposition);
gpBox[gpcount].AutoSize = true;
this.Controls.Add(gpBox[gpcount]);
aCommand3 = new OleDbCommand("select * from batch_tbl where batch_branch LIKE '" + str + "'", main_connection);
aAdapter3 = new OleDbDataAdapter(aCommand3);
ds3 = new DataSet();
aAdapter3.Fill(ds3, "app_info");
ds3.Tables[0].Constraints.Add("pk_bno", ds3.Tables[0].Columns[0], true);
int batch_count = ds3.Tables[0].Rows.Count;
batchCheckBox = new CheckBox[batch_count];
//filling the groupbox with batch code by generating dynamic checkboxes
for (int j=0; j < batch_count; ++j)
{
batchCheckBox[j] = new CheckBox();
batchCheckBox[j].Name = "batch" + Convert.ToString(k);
batchCheckBox[j].Text = ds3.Tables[0].Rows[j][1].ToString();
Console.WriteLine(batchCheckBox[j].Text);
batchCheckBox[j].Location = new System.Drawing.Point(104 * position, 30);
gpBox[gpcount].Controls.Add(batchCheckBox[j]);
batchCheckBox[j].CheckStateChanged += new System.EventHandler(BatchBoxCheckedChanged);
position++;
count++;
Console.WriteLine(batchCheckBox[j].Name);
k++;
}
position = 1;
gpposition += 100;
}
else
{
count--;
this.Controls.RemoveByKey("lbl" + c.Name);
this.Update();
}
}
int total_batch = 1;
string[] batchname;
private void BatchBoxCheckedChanged(object sender, EventArgs e)
{
CheckBox batchBox = (CheckBox)sender;
//Here I want to store name of checkbox in array
if (batchBox.Checked == true)
{
batchname = new String[total_batch];
total_batch++;
}
else
{
}
}

You can try this:
//Gets all checkbox's on the form
List<CheckBox> chks = Controls.OfType<CheckBox>().ToList();
//take only those who is checked, and select only their name property
List<string> names = chks.Where(c => c.Checked).Select(c => c.Name).ToList();
UPDATE
For testing you could print a list of the selected names:
string txt = "";
foreach(string name in names)
{
txt += name+" \n\r";
}
MessageBox.Show(txt);

Thank you everbody
}
list = new List<string>();
}
private void BatchBoxCheckedChanged(object sender, EventArgs e)
{
CheckBox batchBox = (CheckBox)sender;
//Here I want to store name of checkbox in array
if (batchBox.Checked == true)
{
list.Add(batchBox.Text);
}
}
private void button1_Click(object sender, EventArgs e)
{
foreach(string prime in list) // Loop through List with foreach
{
Console.WriteLine(prime);
}
}
This is Done