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Setting up and understanding ContextMenuStrip

first of all:
I´m a student that is still learning about programming.
The problem is that when I right click in a row insde the dataGridView, the RightClickDataView.Items.Add("Abgegeben"); appears as many times as I click. How can I change this?
private void dataGridViewBestellungen_MouseDown(object sender, MouseEventArgs e)
{
if(e.Button == MouseButtons.Right)
{
var hti = dataGridViewBestellungen.HitTest(e.X, e.Y);
dataGridViewBestellungen.Rows[hti.RowIndex].Selected = true;
RightClickDataView.Items.Add("Abgegeben");
RightClickDataView.Show(Cursor.Position);
var xy = dataGridViewBestellungen.SelectedRows;
foreach (DataGridViewRow row in xy)
{
//take the id in the datagridview
}
RightClickDataView.ItemClicked += new ToolStripItemClickedEventHandler(rightclickmenu_ItemClicked);
// close if mouse goes away from window
}
}
private void rightclickmenu_ItemClicked(object sender, ToolStripItemClickedEventArgs e)
{
ToolStripItem item = e.ClickedItem;
dataGridViewBestellungen.ClearSelection();
if (e.ClickedItem.Text == "Zurück")
{
//change the state to erledigt
}
}

Just remove RightClickDataView.Items.Add("Abgegeben"); from your dataGridViewBestellungen_MouseDown and place this line on your constructor for example.

How to link buttons with lines based in graphs

I have a "button creator"(that creates my own custom buttons) in my form and I need to, after creating some buttons in the form, clicking in 2 random ones to connect then with a simple line (can be a System.Drawing.Pen). And i should use some kind of graph logical connection to do it. But I have no idea how I should do. Any code suggestions? Thank You

Here is an example:
// two variables we will need:
Button lastBtn = null;
List<Tuple<Button, Button>> buttons = new List<Tuple<Button, Button>>();
void commonButton_Click(object sender, EventArgs e)
{
Button btn = sender as Button;
if (btn == null) return;
if (lastBtn == null) { lastBtn = btn; return; }
else if (btn == lastBtn) { lastBtn = null; return; }
else { buttons.Add(new Tuple<Button, Button>(lastBtn, btn)); lastBtn = null; }
Invalidate();
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
foreach ( Tuple<Button, Button> t in buttons)
{
e.Graphics.DrawLine(Pens.RoyalBlue, t.Item1.Location, t.Item2.Location);
}
}
When creating your buttons hook each up with the common click event:
yourButtonClass btn = new yourButtonClass()..
..
btn.Click += commonButton_Click;
This always draw lines from and to the upper left corner. Using the middle instead or a smart loaction on an edge the is cloest to the other button if left for you. In the latter case you could also add start- and endcaps to the pen, if you want to.

C# Drag and Drop from one Picture box into Another

I'm working in visual studio 2012 with C# and I need to Drag a Picture box into another picture box, basically replace the target Picturebox Image with the Dragged Picture box image.
How do I do this?
Please be specific and try to explain as simplest and as best as possible.
I'm extremely new to programming, and a bit desperate so please be patient with me.

Drag+drop is hidden on the PictureBox control. Not sure why, it works just fine. The probable guidance here is that it will not be obvious to the user that you could drop an image on the control. You'll have to do something about that, at least set the BackColor property to a non-default value so the user can see it.
Anyhoo, you'll need to implement the MouseDown event on the first picturebox so you can click it and start dragging:
private void pictureBox1_MouseDown(object sender, MouseEventArgs e) {
var img = pictureBox1.Image;
if (img == null) return;
if (DoDragDrop(img, DragDropEffects.Move) == DragDropEffects.Move) {
pictureBox1.Image = null;
}
}
I assumed you wanted to move the image, tweak if necessary if copying was intended. Then you'll have to implement the DragEnter and DragDrop events on the second picturebox. Since the properties are hidden, you should set them in the form's constructor. Like this:
public Form1() {
InitializeComponent();
pictureBox1.MouseDown += pictureBox1_MouseDown;
pictureBox2.AllowDrop = true;
pictureBox2.DragEnter += pictureBox2_DragEnter;
pictureBox2.DragDrop += pictureBox2_DragDrop;
}
void pictureBox2_DragEnter(object sender, DragEventArgs e) {
if (e.Data.GetDataPresent(DataFormats.Bitmap))
e.Effect = DragDropEffects.Move;
}
void pictureBox2_DragDrop(object sender, DragEventArgs e) {
var bmp = (Bitmap)e.Data.GetData(DataFormats.Bitmap);
pictureBox2.Image = bmp;
}
This does allow you to drag an image from another application into the box. Let's call it a feature. Use a bool flag if you want to disallow this.

Hans's answer led me to the correct solution. The problem with that answer is that putting DoDragDrop inside MouseDown will prevent MouseClick events from firing.
Here's my solution:
private void PictureBox_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
var pb = (PictureBox)sender;
if (pb.BackgroundImage != null)
{
pb.DoDragDrop(pb, DragDropEffects.Move);
}
}
}
private void PictureBox_DragEnter (object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Move;
}
private void PictureBox_DragDrop (object sender, DragEventArgs e)
{
var target = (PictureBox)sender;
if (e.Data.GetDataPresent(typeof(PictureBox)))
{
var source = (PictureBox)e.Data.GetData(typeof(PictureBox));
if (source != target)
{
// You can swap the images out, replace the target image, etc.
SwapImages(source, target);
}
}
}
Full working example on my GitHub.

You can use mouse enter and leave events to do this easily. For example you have two picture boxes pictureBox1 and pictureBox2. And you want to drag the image from picture box1 and drop it onto picture box2 do somthing like this.
private void pictureBox2_MouseUp(object sender, MouseEventArgs e)
{
if (a == 1)
{
pictureBox1.Image = pictureBox2.Image;
a = 0;
}
}
private void pictureBox1_MouseEnter(object sender, EventArgs e)
{
a = 1;
}
Where 'a' is just a lock or key which checks whether the mouse has entered the control on which we want to drop this image on. Hope it helped, worked for me.

You can't set AllowDrop on PictureBox...set it for your whole form.
Code Snippet
Form1.AllowDrop = true;
Use the Form DragEnter, DragDrop events, they will work even if you drop it over the pictureBox.
private void Form1_DragEnter(object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Move;
}
private void Form1_DragDrop(object sender, DragEventArgs e)
{
int x = this.PointToClient(new Point(e.X, e.Y)).X;
int y = this.PointToClient(new Point(e.X, e.Y)).Y;
if(x >= pictureBox1.Location.X && x <= pictureBox1.Location.X + pictureBox1.Width && y >= pictureBox1.Location.Y && y <= pictureBox1.Location.Y + pictureBox1.Height)
{
string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
pictureBox1.Image = Image.FromFile(files[0]);
}
}

Drag & Drop between DataGridView

I have copied some code and modified it to suit my application. And I will continue to tweak and clean up the code until I am statisfied with it. But I have encountered a little error. I have two datagridviews and wish to move datagridrows from one to another. However, while the drag&drop events all fire, the dataGridView_Routes_DragDrop() will execute the log command because there is no data in e.Data.GetData. What have I done wrong? Am I missing something? I've tried to look through several guides but nothing specifically covers this issue.
How can I get the datagrid pass the dragged datagridrow over to the other datagrid?
/* Drag & Drop */
private Rectangle dragBoxFromMouseDown;
private int rowIndexFromMouseDown;
private void dataGridView_Trips_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
{
// If the mouse moves outside the rectangle, start the drag.
if (dragBoxFromMouseDown != Rectangle.Empty && !dragBoxFromMouseDown.Contains(e.X, e.Y))
{
// Proceed with the drag and drop, passing in the list item.
DragDropEffects dropEffect = dataGridView_Trips.DoDragDrop(dataGridView_Trips.Rows[rowIndexFromMouseDown], DragDropEffects.Copy);
}
}
}
private void dataGridView_Trips_MouseDown(object sender, MouseEventArgs e)
{
// Get the index of the item the mouse is below.
rowIndexFromMouseDown = dataGridView_Trips.HitTest(e.X, e.Y).RowIndex;
if (rowIndexFromMouseDown != -1)
{
// Remember the point where the mouse down occurred.
// The DragSize indicates the size that the mouse can move
// before a drag event should be started.
Size dragSize = SystemInformation.DragSize;
// Create a rectangle using the DragSize, with the mouse position being
// at the center of the rectangle.
dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2), e.Y - (dragSize.Height / 2)), dragSize);
}
else
// Reset the rectangle if the mouse is not over an item in the ListBox.
dragBoxFromMouseDown = Rectangle.Empty;
}
private void dataGridView_Routes_DragOver(object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Copy;
}
private void dataGridView_Routes_DragDrop(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(typeof(DataRowView)))
{
// The mouse locations are relative to the screen, so they must be
// converted to client coordinates.
Point clientPoint = dataGridView_Routes.PointToClient(new Point(e.X, e.Y));
// If the drag operation was a copy then add the row to the other control.
if (e.Effect == DragDropEffects.Copy)
{
DataGridViewRow rowToMove = e.Data(typeof(DataGridViewRow)) as DataGridViewRow;
dataGridView_Routes.Rows.Add(rowToMove);
}
}
else
{
log("Geen data! #01", "Fout");
}
}
/* End Drag & Drop */

I don't know. But the following function has been adjusted and it works as intended. Not quite sure how the previous code broke.
EDIT: The typeof was written with DataViewRow instead of DataGridViewRow. Fail.
private void dataGridView_Routes_DragDrop(object sender, DragEventArgs e)
{
try
{
if (e.Data.GetDataPresent(typeof(DataGridViewRow)))
{
// The mouse locations are relative to the screen, so they must be
// converted to client coordinates.
Point clientPoint = dataGridView_Routes.PointToClient(new Point(e.X, e.Y));
// If the drag operation was a copy then add the row to the other control.
if (e.Effect == DragDropEffects.Copy)
{
DataGridViewRow Row = (DataGridViewRow)e.Data.GetData(typeof(DataGridViewRow));
dataGridView_Routes.Rows.Add(Row.Cells[0].Value, Row.Cells[1].Value, Row.Cells[2].Value);
}
}
else
{
log("Geen data! #01", "Fout");
}
}
catch (Exception msg)
{
log(msg.Message,"Fout");
}
}

This solution is for the people who have the datagridViews bound to customObjects. It works like a charm with multiple selection. Suggestions are accepted.
Assuming you want to drag from datagridview1 to datagridview2
//datagridview1 is bound to this BindingList
BindingList<myObject> object_bound_list1;
//datagridview2 is bound to this BindingList
BindingList<myObject> object_bound_list2;
List<myObject> selected_Object_list = new List<myObject>();
List<int> selected_pos_list = new List<int>();
private void dataGridView1_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
{
// Proceed with the drag and drop, passing in the list item.
DragDropEffects dropEffect = dataGridView1.DoDragDrop(
selected_Object_list,
DragDropEffects.Move);
}
}
private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
{
// Get the index of the item the mouse is below.
int rowIndexFromMouseDown = dataGridView1.HitTest(e.X, e.Y).RowIndex;
//if shift key is not pressed
if (Control.ModifierKeys != Keys.Shift && Control.ModifierKeys != Keys.Control)
{
//if row under the mouse is not selected
if (!selected_pos_list.Contains(rowIndexFromMouseDown) && rowIndexFromMouseDown > 0)
{
//if there only one row selected
if (dataGridView1.SelectedRows.Count == 1)
{
//select the row below the mouse
dataGridView.ClearSelection();
dataGridView1.Rows[rowIndexFromMouseDown].Selected = true;
}
}
}
//clear the selection lists
selected_Object_list.Clear();
selected_pos_list.Clear();
//add the selected objects
foreach (DataGridViewRow row in dataGridView1.SelectedRows)
{
selected_Object_list.Add(object_bound_list1[row.Index]);
selected_pos_list.Add(row.Index);
}
}
private void dataGridView2_DragOver(object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Move;
}
private void dataGridView2_DragDrop(object sender, DragEventArgs e)
{
if (e.Effect == DragDropEffects.Move)
{
foreach (var item in selected_Object_list)
{
object_bound_list2.Add(item);
}
}
}

How to create a dynamically built Context Menu clickEvent

I have a DataGridView and a context menu that opens when you right click a specific column.
What shows up in the context menu is dependant on what's in the field clicked on - paths to multiple files (the paths are manipulated to create a full UNC path to the correct file).
The only problem is that I can't get the click working.
I did not drag and drop the context menu from the toolbar, I created it programmically.
I figured that if I can get the path (let's call it ContextMenuChosen) to show up in MessageBox.Show(ContextMenuChosen); I could set the same to System.Diagnostics.Process.Start(ContextMenuChosen);
The Mydgv_MouseUp event below actually works to the point where I can get it to fire off MessageBox.Show("foo!"); when something in the context menu is selected but that's where it ends. I left in a bunch of comments below showing what I've tried when it one of the paths are clicked. Some result in empty strings, others error (Object not set to an instance...).
I searched code all day yesterday but couldn't find another way to hook up a dynamically built Context Menu clickEvent.
Code and comments:
ContextMenu m = new ContextMenu();
// SHOW THE RIGHT CLICK MENU
private void Mydgv_MouseClick(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Right)
{
int currentMouseOverCol = Mydgv.HitTest(e.X, e.Y).ColumnIndex;
int currentMouseOverRow = Mydgv.HitTest(e.X, e.Y).RowIndex;
if (currentMouseOverRow >= 0 && currentMouseOverCol == 6)
{
string[] paths = myPaths.Split(';');
foreach (string path in paths)
{
string UNCPath = "\\\\1.1.1.1\\c$\\MyPath\\";
string FilePath = path.Replace("c:\\MyPath\\", #"");
m.MenuItems.Add(new MenuItem(UNCPath + FilePath));
}
}
m.Show(Mydgv, new Point(e.X, e.Y));
}
}
// SELECTING SOMETHING IN THE RIGHT CLICK MENU
private void Mydgv_MouseUp(object sender, MouseEventArgs e)
{
DataGridView.HitTestInfo hitTestInfo;
if (e.Button == MouseButtons.Right)
{
hitTestInfo = Mydgv.HitTest(e.X, e.Y);
// If column is first column
if (hitTestInfo.Type == DataGridViewHitTestType.Cell && hitTestInfo.ColumnIndex == 6)
{
//MessageBox.Show(m.ToString());
////MessageBox.Show(m.Tag.ToString());
//MessageBox.Show(m.Name.ToString());
//MessageBox.Show(m.MenuItems.ToString());
////MessageBox.Show(m.MdiListItem.ToString());
// MessageBox.Show(m.Name);
//if (m.MenuItems.Count > 0)
//MessageBox.Show(m.MdiListItem.Text);
//MessageBox.Show(m.ToString());
//MessageBox.Show(m.MenuItems.ToString());
//Mydgv.ContextMenu.Show(m.Name.ToString());
//MessageBox.Show(ContextMenu.ToString());
//MessageBox.Show(ContextMenu.MenuItems.ToString());
//MenuItem.text
//MessageBox.Show(this.ContextMenu.MenuItems.ToString());
}
m.MenuItems.Clear();
}
}
I'm very close to completing this so any help would be much appreciated.

I don't see an event handler wired to your menu item, so that something will happen when you click it:
void menu_Click(object sender, EventArgs e) {
MessageBox.Show(((MenuItem)sender).Text);
}
Then attach it when you add the menu item to the context menu:
MenuItem mi = new MenuItem(UNCPath + FilePath);
mi.Click += menu_Click;
m.MenuItems.Add(mi);

You may handle CellMouseDown like this when you when you right click a cell of a specific column. The specific column is achieved by e.ColumnIndex check
Aditionally, you can use GetCellDisplayRectangle instead of hittest
ContextMenu cm = new ContextMenu();
void dataGridView1_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
{
if (e.Button == MouseButtons.Right)
{
if (e.ColumnIndex == 0)
{
cm.MenuItems.Clear();
var mi = new MenuItem("C:\temp");
mi.MenuItems.Add(mi);
// handle menu item click event here [as required]
mi.Click += OnMenuItemClick;
cm.MenuItems.Add(0, mi);
var bounds = dataGridView1.GetCellDisplayRectangle(e.ColumnIndex, e.RowIndex, false);
if (sender != null)
{
cm.Show(sender as DataGridView, new Point(bounds.X, bounds.Y));
}
}
}
}
void OnMenuItemClick(object sender, EventArgs e)
{
MessageBox.Show(((MenuItem)sender).Text);
}