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How to get coordinates of a Mouse when it's Clicked

I'm beginner in c# and need some help. After loading Form I want to display on Form coordinates of a Mouse when it's Clicked. Click can be made outside of the Form. For example in Browser. Can someone help me with this.

Maybe the most simple way is setting Capture property of a form to true, then handle click event and convert the position (that is position related to top left point of form) to screen position using PointToScreen method of form.
For example you can put a button on form and do:
private void button1_Click(object sender, EventArgs e)
{
//Key Point to handle mouse events outside the form
this.Capture = true;
}
private void MouseCaptureForm_MouseDown(object sender, MouseEventArgs e)
{
this.Activate();
MessageBox.Show(this.PointToScreen(new Point(e.X, e.Y)).ToString());
//Cursor.Position works too as RexGrammer stated in his answer
//MessageBox.Show(this.PointToScreen(Cursor.Position).ToString());
//if you want form continue getting capture, Set this.Capture = true again here
//this.Capture = true;
//but all clicks are handled by form now
//and even for closing application you should
//right click on task-bar icon and choose close.
}
But more correct (and slightly difficult) way is using global hooks.
If you really need to do it, you can take a look at this links:
Processing Global Mouse and Keyboard Hooks in C#
Low-Level Mouse Hook in C#
Application and Global Mouse and Keyboard Hooks .Net Libary in C#

I think you can't handle the mouse click outside your Form at least easily.
inside the form using MouseEventArgs it can simply be handled.
private void Form1_MouseClick(object sender, MouseEventArgs e)
{
// e.Location.X & e.Location.Y
}
Learn more about this topic at Mouse Events in Windows Forms.
I hope it helps.

Cursor.Position and Control.MousePosition both return the position of the mouse cursor in screen coordinates.
The following articles deal with capturing Global mouse click events:
Processing Global Mouse and Keyboard Hooks in C#
Global Windows Hooks

You need a global mouse hook.
See this question

Object stops tracking mouse position when hovering over other objects C#

I have a program which uses the mouse's .X position (relative to the form boundaries) to change the .Left value of a button Object.
The problem is that I have this button over the top of other objects like Picture Boxes, Buttons, TrackBar's etc. and when I hove over these other elements, the button stops tracking the mouse's .X position.
How can I make the button track the mouse movement regardless of the mouse doing other stuff on the form too? (I also need to interact with the other elements at the same time too).
My Code:
/* i create the mousemove tracking event */
this.MouseMove += new MouseEventHandler(btnBat1_MouseMove);
/* and use it by making a new method */
public void btnBat1_MouseMove(Object sender, MouseEventArgs e)
{
// I use the variable mouseXCo to change the button1.Left value.
mouseXCo = e.X;
}
Thanks in advance guys :-)

Getting the scrolling offset when storing coordinates

I am working on a Form that takes and draws a point on a mouse click. I am confused about how to properly get and add the scrolling offset so that the points can be drawn correctly. For example, right now when I add a point where the upper left coordinate is (0,0), the point redraws itself and moves with the scrolling action instead of staying at the spot it was originally created at. I have set
this.AutoScroll = true
and have set the minimum size manually
this.AutoScrollMinsSize = new Size(800,600);
Here is what my mouse click event looks like so far:
if (e.Button == MouseButtons.Left)
{
Point newPoint = new Point(e.X, e.Y);
p.X += this.AutoScrollOffset.X;
p.Y += this.AutoScrollOffset.Y;
this.Invalidate();
}
What is the proper way to use the AutoScrollOffset property to keep the points where they belong instead of moving as I scroll?
I should add that my program also overrides the Scroll event to repaint when a scroll event occurs to fix the problem of a drawing disappearing once the visible area was left.

AutoScrollOffset is not the correct property to use. It has very limited use, it can apply an offset to the scroll position when the ScrollControlIntoView() method is used. Which is pretty rare, never once used it myself.
You need to use the AutoScrollPosition property instead:
if (e.Button == MouseButtons.Left) {
var newPoint = new Point(e.X - this.AutoScrollPosition.X,
e.Y - this.AutoScrollPosition.Y);
// etc..
}
Note that substraction is required, a bit unintuitive.

Mouse Click Location On A PictureBox Not Detected Within Label

I have a Form that contains only 2 things, a PictureBox and a Label.
I added a mouse click event handler to the picture box.
this.pictureBox1.MouseClick += picture_MouseClick;
Inside the handler I need to check if the location of the mouse click is within the bounds of the label. To do this, I am using the mouse event location and checking to see whether that location is within the bounds of the label.
private void picture_MouseClick(object sender, MouseEventArgs e)
{
if (label1.Bounds.Contains(e.Location))
{
MessageBox.Show("FOUND YOU!");
}
}
I expected this to work as it seems easy enough however the click location (the orange box in the image) that leads to the MessageBox being shown is offset down and to the right of the label.
Is this because the mouse event is relative to the PictureBox and the Label bounds are relative to the Form? Or vice versa?
By the way, the label you see in the image is hidden at runtime. I am just using the label as a "hack" way of knowing if the user clicked in a certain spot.
public Form1()
{
InitializeComponent();
this.label1.Visible = false;
this.pictureBox1.MouseClick += picture_MouseClick;
}
(I tried subtracting the width of the label from e.X and the height of the label from e.Y but that didn't seem to work.)
Thank you,
Jan

The e.Location is the mouse position (a point) relative to the upper-left corner of the picturebox.
The Bounds property is relative to the container of the control.
(And in this case, the container is the form, as you and SLacks have rightly pointed out)
To check the correct position I will try with this code (now tested)
Point p = e.Location;
p.X += pictureBox1.Left;
p.Y += pictureBox1.Top;
if(label1.Bounds.Contains(p))
.....

WPF drag distance threshold

I have a program with two WPF treeviews that allow dragging and dropping between the two. The problem is, it can be annoying to open / close items on the treeviews because moving the mouse just one pixel while holding the left mouse button triggers the drag / drop functionality. Is there some way to specify how far the mouse should move before it's considered a drag / drop?

There's a system parameter for this. If you have
Point down = {where mouse down event happened}
Point current = {position in the MouseMove eventargs}
then the mouse has moved the minimum drag distance if
Math.Abs(current.X - down.X) >= SystemParameters.MinimumHorizontalDragDistance ||
Math.Abs(current.Y - down.Y) >= SystemParameters.MinimumVerticalDragDistance

Just build a little buffer into your code that determines when the drag starts.
flag mouse down
on mouse move - check for mouse down.. if yes, check to see if its moved farther than whatever buffer you specify (3 pixels is probably good)
if it has, start the drag.

Following this article for Drag and Drop implementation, you would have to handle 2 mouse events in order to delay the dragging until the mouse has moved a certain distance. First, add a handler for PreviewMouseDown which stores the initial mouse position relative to your control. Don't use the MouseDown event because it is a bubbling event and may have been handled by a child control before reaching your control.
public class DraggableControl : UserControl
{
private Point? _initialMousePosition;
public DraggableControl()
{
PreviewMouseDown += OnPreviewMouseDown;
}
private void OnPreviewMouseDown(object sender, MouseButtonEventArgs e) {
_initialMousePosition = e.GetPosition(this);
}
Additionally, handle MouseMove to check the moved distance and eventually initiate the drag operation:
...
public DraggableControl()
{
...
MouseMove += OnMouseMove;
}
...
private void OnMouseMove(object sender, MouseEventArgs e)
{
// Calculate distance between inital and updated mouse position
var movedDistance = (_initialMousePosition - e.GetPosition(this)).Length;
if (movedDistance > yourThreshold)
{
DragDrop.DoDragDrop(...);
}
}
}