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Transfer values from one class to another using a list

I am facing a problem in my winforms app I am building in Visual Studio 2019. My app has 8 forms and I constructed a new class in which I want to save the name of the forms that users visited through a list and save them in a .txt file. I am providing you the pieces of code that I am trying to implement.
Code of one of 8 forms
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SQLite;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Speech.Synthesis;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Delfoi_Tourist_Guide
{
public partial class Welcome : Form
{
SQLiteConnection connection;
private SpeechSynthesizer speech = new SpeechSynthesizer();
public Welcome()
{
InitializeComponent();
User_History.HistList.Add(this.Name);
User_History.SaveHistory();
}
private void Welcome_Load(object sender, EventArgs e)
{
String conn = "Data Source=Delfoidb1.db;Version=3";
connection = new SQLiteConnection(conn);
connection.Open(); //or Create Database
}
private void Timer1_Tick(object sender, EventArgs e)
{
label1.Show();
label2.Show();
button1.Visible = true;
button2.Visible = true;
timer2.Enabled = true;
timer1.Enabled = false;
}
private void button1_Click(object sender, EventArgs e)
{
if (speech.State == SynthesizerState.Speaking)
{
speech.Pause();
}
Form2 form2 = new Form2();
form2.Show();
this.Visible = false;
}
private void button6_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void timer2_Tick(object sender, EventArgs e)
{
speech.SelectVoice("Microsoft Stefanos");
speech.SpeakAsync(label2.Text);
timer2.Enabled = false;
}
private void button2_Click(object sender, EventArgs e)
{
if (speech.State == SynthesizerState.Speaking)
{
speech.Pause();
}
Form8 form8 = new Form8();
form8.Show();
this.Visible = false;
}
private void aboutToolStripMenuItem1_Click(object sender, EventArgs e)
{
MessageBox.Show("Developed by Ανδρέας Κρεούζος(ΜΠΠΛ20040) and Δημήτρης Γιογάκης(ΜΠΠΛ20008)");
}
private void helpToolStripMenuItem_Click(object sender, EventArgs e)
{
//Implement try - catch to avoid exception specifically for url error
try
{
Help.ShowHelp(this, "_tmphhp/Delfoi_Tourist_Guide_Help.chm", HelpNavigator.KeywordIndex, "Topic 1");
}
catch (Exception exception)
{
MessageBox.Show(exception.ToString());
}
}
private void aboutToolStripMenuItem_Click(object sender, EventArgs e)
{
if (speech.State == SynthesizerState.Speaking)
{
speech.Pause();
}
Welcome welcome = new Welcome();
welcome.Show();
this.Visible = false;
}
private void έξοδοςToolStripMenuItem_Click(object sender, EventArgs e)
{
Application.Exit();
}
}
}
Code of the separate class that saves the data as txt
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Delfoi_Tourist_Guide
{
public static class User_History
{
public static List<string> HistList = new List<string>();
public static void SaveHistory()
{
SaveFileDialog saveFileDialog = new SaveFileDialog();
if (saveFileDialog.ShowDialog() == DialogResult.OK)
{
string path = saveFileDialog.FileName;
StreamWriter sw = new StreamWriter(path);
sw.WriteLine(HistList);
sw.Close();
}
}
}
}
My problem is that I can't transfer the data (placed on the InitializeComponent) from forms to my class. I am getting my txt file with nothing in it. My data is actually saved on my public static list but I can't transfer it next to the rest of my User_History class.
Any ideas on how to accomplish this???

You can try this SaveHistory() method
public static void SaveHistory()
{
SaveFileDialog saveFileDialog = new SaveFileDialog();
if (saveFileDialog.ShowDialog() == DialogResult.OK)
{
string path = saveFileDialog.FileName;
using (StreamWriter writer = new StreamWriter(path, false))
{
foreach (string history in HistList)
{
writer.WriteLine(history);
}
}
}
}

how to handle multiple events on forms in c#

in my current project ,i have a form which contains 2 command buttons named COPY and Cancel
if i click COPY button it is copying 3000 files from source directory to a destination directory ,at the same time if click the Cancel Button , it should cancel the copy and exit the form. is there any way to do so?
i applied the solution but got errors. i have the following code
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Threading;
namespace WindowsFormsApplication8
{
public partial class Form1 : Form
{
private volatile bool _continue = false;
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
_continue = true;
System.Threading.ThreadStart ts = new ThreadStart(print_number);
System.Threading.Thread t = new Thread(ts);
t.Start();
}
private void print_number()
{
for (int i = 1; i <= 10000; i++)
{
textBox1.Text = Convert.ToString(i);
if (_continue == false)
{
return;
}
//Thread.Sleep(2000);
}
}
private void button2_Click(object sender, EventArgs e)
{
_continue = false;
Close();
}
}
}

Example:
private volatile bool _continue = false;
private void CopyClicked(Object sender, EventArgs e)
{
_continue = true;
System.Threading.ThreadStart ts = new ThreadStart(CopyFiles);
System.Threading.Thread t = new Thread(ts);
t.Start();
}
private void CopyFiles(){
List<String> list = GetFileNames();
foreach( String f in list )
{
if ( _continue == false )
{
return;
}
CopyFile(s); //examples...
}
}
private void CancelClicked(Object sender, EventArgs e)
{
_continue = false;
Close();
}

Windows Forms text editor search function

I have two forms, one is for the text editor, and the second is for the search form.
In my Form1 I have defined the GetRichTextBox() function. It works there, how could I retrieve it to Form2 (and the other stuff)?
My Form1:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace TextEditor
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private RichTextBox GetRichTextBox()
{
RichTextBox rtb = null;
TabPage tp = tabControl1.SelectedTab;
if (tp != null)
{
rtb = tp.Controls[0] as RichTextBox;
}
return rtb;
}
private void newToolStripMenuItem_Click(object sender, EventArgs e)
{
TabPage tp = new TabPage("doc");
RichTextBox rtb = new RichTextBox();
rtb.Dock = DockStyle.Fill;
tp.Controls.Add(rtb);
tabControl1.TabPages.Add(tp);
}
private void cutToolStripMenuItem_Click(object sender, EventArgs e)
{
GetRichTextBox().Cut();
}
private void copyToolStripMenuItem_Click(object sender, EventArgs e)
{
GetRichTextBox().Copy();
}
private void pasteToolStripMenuItem_Click(object sender, EventArgs e)
{
GetRichTextBox().Paste();
}
private void undoToolStripMenuItem_Click(object sender, EventArgs e)
{
GetRichTextBox().Undo();
}
private void redoToolStripMenuItem_Click(object sender, EventArgs e)
{
GetRichTextBox().Redo();
}
private void openToolStripMenuItem_Click(object sender, EventArgs e)
{
OpenFileDialog openFD = new OpenFileDialog();
string Chosen_File = "";
openFD.InitialDirectory = "C:";
openFD.Title = "Open a Text File";
openFD.FileName = "";
openFD.Filter = "Text Files|*.txt|Word Documents|*.doc";
if (openFD.ShowDialog() != DialogResult.Cancel)
{
Chosen_File = openFD.FileName;
TabPage tab = new TabPage() { Text = System.IO.Path.GetFileName(Chosen_File) };
tabControl1.TabPages.Add(tab);
tabControl1.SelectedTab = tab;
RichTextBox box = new RichTextBox { Parent = tab, Dock = DockStyle.Fill };
box.LoadFile(Chosen_File, RichTextBoxStreamType.PlainText);
}
}
private void saveToolStripMenuItem_Click(object sender, EventArgs e)
{
SaveFileDialog saveFD = new SaveFileDialog();
string saved_file = "";
saveFD.InitialDirectory = "C:";
saveFD.Title = "Save a Text File";
saveFD.FileName = "";
saveFD.Filter = "Text Files|*.txt|Word Documents|*.doc";
if (saveFD.ShowDialog() != DialogResult.Cancel)
{
saved_file = saveFD.FileName;
GetRichTextBox().SaveFile(saved_file, RichTextBoxStreamType.PlainText);
MessageBox.Show("Your file has been successfully saved!", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
if (MessageBox.Show("Are you sure?", "Exit", MessageBoxButtons.OKCancel) == DialogResult.OK)
{
Application.Exit();
}
}
private void closeTabToolStripMenuItem_Click(object sender, EventArgs e)
{
TabPage active_tab = tabControl1.SelectedTab;
tabControl1.TabPages.Remove(active_tab);
}
private void searchToolStripMenuItem_Click(object sender, EventArgs e)
{
var search = new Form2();
search.ShowDialog();
}
}
}
And ofcourse, my Form2:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace TextEditor
{
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
int index = 0; string temp = richTextBox1.Text; richTextBox1.Text = ""; richTextBox1.Text = temp;
while (index < richTextBox1.Text.LastIndexOf(textBox1.Text))
{
richTextBox1.Find(textBox1.Text, index, richTextBox1.TextLength, RichTextBoxFinds.None);
richTextBox1.SelectionBackColor = Color.Orange;
index = richTextBox1.Text.IndexOf(textBox1.Text, index) + 1;
}
}
}
}

Copy text from listview into another winform

I am really stuck with this so I hope someone can help. I have 2 winforms, one has a listview and another has a textbox. I want to check which item is checked in the listview and copy this text into the second form. I have tried this code but it won't work, any help is greatly appreciated!
// 1st form
private void button5_Click(object sender, EventArgs e) // Brings up the second form
{
Form4 editItem = new Form4();
editItem.Show();
}
public string GetItemValue()
{
for (int i = 0; i < listView1.Items.Count; i++)
{
if (listView1.Items[i].Checked == true)
{
return listView1.Items[i].Text;
}
}
return "Error";
}
// 2nd form
private void Form4_Load(object sender, EventArgs e)
{
Form1 main = new Form1();
textBox1.Text = main.GetItemValue();
}

You are creating a new Form1 inside of Form4 after it has been loaded. You need a reference to the original Form1. This can be accomplished in several ways, probably the easiest is passing a reference into the Form4 constructor.
// Form 1
// This button creates a new "Form4" and shows it
private void button5_Click(object sender, EventArgs e)
{
Form4 editItem = new Form4(this);
editItem.Show();
}
public string GetItemValue()
{
for (int i = 0; i < listView1.Items.Count; i++)
{
if (listView1.Items[i].Checked == true)
{
return listView1.Items[i].Text;
}
}
return "Error";
}
--
// Form 2 (Form4)
// Private member variable / reference to a Form1
private Form1 _form;
// Form4 Constructor: Assign the passed-in "Form1" to the member "Form1"
public Form4(Form1 form)
{
this._form = form;
}
// Take the member "Form1," get the item value, and write it in the text box
private void Form4_Load(object sender, EventArgs e)
{
textBox1.Text = this._form.GetItemValue();
}

You only need a couple of changes. No need to add your own way of storing the owner form as this functionality already exists.
private void button5_Click(object sender, EventArgs e) // Brings up the second form
{
Form4 editItem = new Form4();
editItem.Show(this); //passes a reference to this form to be stored in owner
}
Then reference it on the other form.
private void Form4_Load(object sender, EventArgs e)
{
textBox1.Text = ((Form1)owner).GetItemValue();
}

Try thisway
FORM 1
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
//Fields
public List<string> itemTexts;
public Form1()
{
InitializeComponent();
//Generate some items
for (int i = 0; i < 10; i++)
{
ListViewItem item = new ListViewItem();
item.Text = "item number #" + i;
listView1.Items.Add(item);
}
}
private void button1_Click(object sender, EventArgs e)
{
foreach (ListViewItem item in listView1.Items)
{
if (item.Checked)
{
itemTexts.Add(item.Text);
}
}
Form2 TextBoxForm = new Form2(itemTexts);
TextBoxForm.Show();
}
}
}
FORM 2
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form2 : Form
{
//Fields
List<string> itemTexts;
public Form2(List<string> itemTexts)
{
InitializeComponent();
this.itemTexts = itemTexts;
foreach (string text in itemTexts)
{
textBox1.Text += text + Environment.NewLine;
}
}
}
}

How can I show map on gMapControl?

My problem is I can not see any thing on form when I run application. This my code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using GMap;
using GMap.NET;
using GMap.NET.WindowsForms;
namespace Gmap_tesx
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e1)
{
try
{
System.Net.IPHostEntry e =
System.Net.Dns.GetHostEntry("www.google.com");
}
catch
{
gMapControl1.Manager.Mode = AccessMode.CacheOnly;
MessageBox.Show("No internet connection avaible, going to CacheOnly mode.",
"GMap.NET - Demo.WindowsForms", MessageBoxButtons.OK,
MessageBoxIcon.Warning);
}
// config map
GMaps.Instance.Mode = AccessMode.ServerAndCache;
// gMapControl1.CacheLocation = Application.StartupPath + "data.gmdp";
GMaps g = new GMaps();
gMapControl1.MapType = MapType.GoogleSatellite;
gMapControl1.MaxZoom = 6;
gMapControl1.MinZoom = 1;
gMapControl1.Zoom = gMapControl1.MinZoom + 1;
gMapControl1.Position = new PointLatLng(54.6961334816182,
25.2985095977783);
// map events
gMapControl1.OnCurrentPositionChanged += new
CurrentPositionChanged(gMapControl1_OnCurrentPositionChanged);
gMapControl1.OnTileLoadStart += new TileLoadStart(gMapControl1_OnTileLoadStart);
gMapControl1.OnTileLoadComplete += new
TileLoadComplete(gMapControl1_OnTileLoadComplete);
gMapControl1.OnMarkerClick += new MarkerClick(gMapControl1_OnMarkerClick);
gMapControl1.OnMapZoomChanged += new MapZoomChanged(gMapControl1_OnMapZoomChanged);
gMapControl1.OnMapTypeChanged += new MapTypeChanged(gMapControl1_OnMapTypeChanged);
gMapControl1.MouseMove += new MouseEventHandler(gMapControl1_MouseMove);
gMapControl1.MouseDown += new MouseEventHandler(gMapControl1_MouseDown);
gMapControl1.MouseUp += new MouseEventHandler(gMapControl1_MouseUp);
gMapControl1.OnMarkerEnter += new MarkerEnter(gMapControl1_OnMarkerEnter);
gMapControl1.OnMarkerLeave += new MarkerLeave(gMapControl1_OnMarkerLeave);
}
private void gMapControl1_OnCurrentPositionChanged(PointLatLng point)
{
}
private void gMapControl1_OnMarkerLeave(GMapMarker item)
{
}
private void gMapControl1_OnMarkerEnter(GMapMarker item)
{
}
private void gMapControl1_MouseUp(object sender, MouseEventArgs e)
{
}
private void gMapControl1_MouseDown(object sender, MouseEventArgs e)
{
}
private void gMapControl1_MouseMove(object sender, MouseEventArgs e)
{
}
private void gMapControl1_OnMapTypeChanged(MapType type)
{
}
private void gMapControl1_OnMapZoomChanged()
{
}
private void gMapControl1_OnMarkerClick(GMapMarker item, MouseEventArgs e)
{
}
private void gMapControl1_OnTileLoadComplete(long ElapsedMilliseconds)
{
}
private void gMapControl1_OnTileLoadStart()
{
}
}
}