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Showing starting text of Mulitline TextBox when focus is changed

I am creating a form which has a Multiline TextBox to enter an URL. Expected URLs will be very long.
User will paste the URL and move to next box.
Right now, TextBox shows ending part of the URL when user moves to next TextBox. I want such that it will show starting of URL (Domain name) instead of trailing part.
Current:
Expected:
And this should happen when user leaves the TextBox.
I tried various methods of Selection in textBox_Leave() event but I guess, these methods won't work if focus is lost.
I am using .Net framework 3.5.
Update: Textbox I am using is Multiline. Answers suggested by #S.Akbari and #Szer are perfect if the Mutliline property is set to False. I realized it late that Multiline will play such a significant role. Hence updating the question!

Use SelectionStart in the Leave event should works:
private void textBox1_Leave(object sender, EventArgs e)
{
textBox1.SelectionStart = 0;
}
Before:
After leaving TextBox:

Tried it and it works. Proof
public Form1()
{
InitializeComponent();
textBox1.LostFocus += TextBox1_LostFocus;
}
private void TextBox1_LostFocus(object sender, EventArgs e)
{
textBox1.SelectionStart = 0;
textBox1.SelectionLength = 0;
}

I can see how it doesn't work with the Multiline property set to true.
A simple API call can make this work:
[DllImport("user32.dll", CharSet = CharSet.Auto)]
private static extern int SendMessage(IntPtr hWnd, int wMsg, IntPtr wParam, IntPtr lParam);
private const int WM_VSCROLL = 0x115;
private const int SB_TOP = 6;
void textBox1_Leave(object sender, EventArgs e) {
SendMessage(textBox1.Handle, WM_VSCROLL, (IntPtr)SB_TOP, IntPtr.Zero);
}

Adding scroll bar to windows forms, c#

I need to add scroll horizontal and vertical scroll bar. The problem is that they doesn't work, as in when I use them the screen doesn't move.
VScrollBar vScrollBar1 = new VScrollBar();
HScrollBar hScrollBar1 = new HScrollBar();
vScrollBar1.Dock = DockStyle.Left;
hScrollBar1.Dock = DockStyle.Bottom;
Controls.Add(vScrollBar1);
Controls.Add(hScrollBar1);
I use the code to add scroll bars, how do I activate them or get them to work as I need?
Thanks!

You usually don't add Scrollbars; you set AutoScroll = true in the form's property panel.
Now when any control grows out of the Form or is moved over right or bottom border the Form will show the necessary Scrollbar.
You can test it with a Label and a TextBox: Set the Label to the right border and script the TextBox's TextChanged event like this:
private void textBox1_TextChanged(object sender, EventArgs e)
{
label1.Text = textBox1.Text;
}
Now run the programm and enter stuff into the Textbox; you will observe how the Label grows and how the Form brings up a horizontal Scrollbar when it goes over the edge.
Note 1: This will not work if the Form has AutoSize = true - then instead the form will grow! If the Form has both AutoSize and AutoScroll true, then AutoSize will win.
Note 2: This test will only work if the Label has AutoSize = true, as it has by default..

You need to use the Panel control as container of your child controls and set "AutoScroll" property to true.
Set true to AutoScroll property of Form.
Write this code in your Form Load Event, and you will get your scroll bar, like I am writing it here in my Form Load Event.
private void Form1_Load(object sender, EventArgs e)
{
Panel my_panel = new Panel();
VScrollBar vScroller = new VScrollBar();
vScroller.Dock = DockStyle.Right;
vScroller.Width = 30;
vScroller.Height = 200;
vScroller.Name = "VScrollBar1";
my_panel.Controls.Add(vScroller);
}

vScrollbars and hScrollbars are just plain controls without code. [UI]
You need to code to make them do something!
Or just set the property 'AutoScroll = true;' in your form or add a panel and set it to true.
However your control needs Focus() to scroll with your mouse wheel.
Here is a little workaround:
public Main()
{
InitializeComponent();
//Works for panels, richtextboxes, 3rd party etc..
Application.AddMessageFilter(new ScrollableControls(panel1, richtextbox1, radScrollablePanel1.PanelContainer));
}
ScrollableControls.cs:
using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
//Let controls scroll without Focus();
namespace YOURNAMESPACE
{
internal struct ScrollableControls : IMessageFilter
{
private const int WmMousewheel = 0x020A;
private readonly Control[] _controls;
public ScrollableControls(params Control[] controls)
{
_controls = controls;
}
bool IMessageFilter.PreFilterMessage(ref Message m)
{
if (m.Msg != WmMousewheel) return false;
foreach (var item in _controls)
{
ScrollControl(item, ref m);
}
return false;
}
[DllImport("user32.dll")]
private static extern int SendMessage(IntPtr hWnd, int msg, int wParam, int lParam);
private static void ScrollControl(Control control, ref Message m)
{
if (control.RectangleToScreen(control.ClientRectangle).Contains(Cursor.Position) && control.Visible)
{
SendMessage(control.Handle, m.Msg, m.WParam.ToInt32(), m.LParam.ToInt32());
}
}
}
}

Drag form with control from another class

Firstly, I apologize if the title does not make much sense, as I did not know the best way to explain it.
Now to really explain it. What I have done is created a control in a Class Library project in Visual Studio 2013. This control is supposed to act as the caption bar for form that is set with the "FormBorderStyle" as "None". This imitation caption bar control is supposed to move the form, just like a normal forms' caption bar would.
I have achieved this, but only in the forms code. This is the code I use:
private int mouseStartX, mouseStartY;
private int formStartX, formStartY;
private bool FormDragging = false;
private void titleBar_MouseDown(object sender, MouseEventArgs e)
{
this.mouseStartX = MousePosition.X;
this.mouseStartY = MousePosition.Y;
this.formStartX = this.Location.X;
this.formStartY = this.Location.Y;
FormDragging = true;
}
private void titleBar_MouseMove(object sender, MouseEventArgs e)
{
if (FormDragging)
{
this.Location = new Point(
this.formStartX + MousePosition.X - this.mouseStartX,
this.formStartY + MousePosition.Y - this.mouseStartY
);
}
}
private void titleBar_MouseUp(object sender, MouseEventArgs e)
{
FormDragging = false;
}
"this.*" is obviously referring to the form, when in the forms code. So of course, if I were to simply put this into the controls code, it'd obviously be referring to the control, and thus the control would be the one moving around on the form.
I've also created a control in the Class Library that acts as a close button. All I had to do was:
Form.ActiveForm.Close();
Same for minimize being:
Form.ActiveForm.WindowState = FormWindowState.Minimized;
And maximize being:
Form.ActiveForm.WindowState = FormWindowState.Maximized;
On the controls' click events.
When I try to replace "this." with "Form.ActiveForm.", in the first code posted - it returns this error:
'System.Windows.Forms.Form' does not contain a definition for 'mouseStarX' and no extension method 'mousStartX' accepting a first argument of type 'System.Windows.Forms.Form' could be found (are you missing a using directive or an assembly reference?)
That's about it, I don't know how else to go about this.

There is a simple pinvoke you can use to move the form via your control.
Adapted from C# - Make a borderless form movable?, instead of using Form.ActiveForm, you would use this.FindForm() to get the parent form of the control. It's used here to pass the form's handle value:
public class MyHeader : Control {
private const int WM_NCLBUTTONDOWN = 0xA1;
private const int HT_CAPTION = 0x2;
[DllImportAttribute("user32.dll")]
private static extern int SendMessage(IntPtr hWnd, int Msg,
int wParam, int lParam);
[DllImportAttribute("user32.dll")]
private static extern bool ReleaseCapture();
protected override void OnMouseDown(MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
ReleaseCapture();
SendMessage(this.FindForm().Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);
}
base.OnMouseDown(e);
}
}
For closing the form, you would use the same method:
this.FindForm().Close();

C# - Fix linklabel hand-cursor

I have two link labels in my windows forms program which links to my website.
I got rid of the underlines and the ugly blue colour and tried to fix them up a little bit.
But the biggest problem still remains and It's just so disturbing for me, I don't know why.
The hand cursor when you hover over them is that old Windows 98 hand/link cursor.
Is there any way to change it to the system cursor?
I've checked some other links about this problem, but I couldn't get it to work so I decided to ask here.
Here's my code to get rid of the underline btw:
linkLabel1.LinkBehavior = System.Windows.Forms.LinkBehavior.NeverUnderline;

Unfortunately the LinkLabel class is hard-coded to use Cursors.Hand as the hover cursor.
However, you can work around it by adding a class like this to your project:
public class MyLinkLabel : LinkLabel
{
protected override void OnMouseEnter(EventArgs e)
{
base.OnMouseEnter(e);
OverrideCursor = Cursors.Cross;
}
protected override void OnMouseLeave(EventArgs e)
{
base.OnMouseLeave(e);
OverrideCursor = null;
}
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
OverrideCursor = Cursors.Cross;
}
}
and using that instead of LinkLabel on your form. (This sets the cursor to a cross for testing purposes, but you can change it to whatever you want.)
I should say that the real LinkLabel code has much more complex logic to do with changing the cursor according to whether or not the link is enabled, but you might not care about that.

Set the Cursor property to Arrow in the properties pane of the LinkLabel in Visual Studio

Update
I prefer Hamido-san's answer here. His solution works properly when the LinkLabel is set to AutoSize = false and works with a LinkArea.
Old solution:
public class LnkLabel : LinkLabel
{
const int WM_SETCURSOR = 32,
IDC_HAND = 32649;
[DllImport("user32.dll")]
public static extern int LoadCursor(int hInstance, int lpCursorName);
[DllImport("user32.dll")]
public static extern int SetCursor(int hCursor);
protected override void WndProc(ref Message m)
{
if (m.Msg == WM_SETCURSOR)
{
int cursor = LoadCursor(0, IDC_HAND);
SetCursor(cursor);
m.Result = IntPtr.Zero; // Handled
return;
}
base.WndProc(ref m);
}
}

Maximizing a custom window to include taskbar

I made a custom window for my app and I wrote some code if a user clicks my custom maximize button:
private void MaxThis(object sender, System.Windows.RoutedEventArgs e)
{ if (WindowState == WindowState.Maximized){
WindowState = WindowState.Normal;}
else {
this.Top = 0;
this.Left = 0;
this.MaxWidth = System.Windows.SystemParameters.WorkArea.Width;
this.MaxHeight = System.Windows.SystemParameters.WorkArea.Height;
this.WindowState = WindowState.Maximized;
}
}
The restoring to the normal state works fine. However when I want to maximize, it maximizes the window with a small margin on the right and bottom of the screen. Clicking maximize again fixes this somehow. How do I fix this to maximize at the first click...?

Take away the Height and Width properties you have set in XAML for your window

Try to use just
this.WindowState = WindowState.Maximized;
Perhaps code, goes before messing Windows API action.
Sorry, my mistake.
Then you should use Windows API to raise Maximize event.
Try this code:
[DllImport("user32.dll")]
public static extern int SendMessage(
int hWnd, // handle to destination window
uint Msg, // message
long wParam, // first message parameter
long lParam // second message parameter
);
public const int WM_SIZE = 0x0005;
public const int SIZE_MAXIMIZED = 2;
And in your click event:
SendMessage(this.Handle, WM_SIZE, SIZE_MAXIMIZED, 0);