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How to set the minimum size to restrict the resizing?

i have used the user control. i have also set the minimum size to the user control. i have used the following codes to enable the resizing..
private const int cGrip = 16; // Grip size
private const int cCaption = 32; // Caption bar height;
protected override void WndProc(ref Message m)
{
if (m.Msg == 0x84)
{
// Trap WM_NCHITTEST
System.Drawing.Point pos = new System.Drawing.Point(m.LParam.ToInt32() & 0xffff, m.LParam.ToInt32() >> 16);
pos = this.PointToClient(pos);
if (pos.Y < cCaption)
{
m.Result = (IntPtr)2; // HTCAPTION
return;
}
if (pos.X >= this.MinimumSize.Width - cGrip && pos.Y >= this.MinimumSize.Height - cGrip)
{
m.Result = (IntPtr)17; // HTBOTTOMRIGHT
return;
}
}
base.WndProc(ref m);
}
But its not working to set the minimum size. its resizing to size as 0.please refer the below image. i want to set the minimum size to restrict the resizing. please suggest any solutions?

I haven't completely understood what you are trying to achieve. But, if you are populating your UserControl in a Windows Forms, simply set the MinimumSize property of the control. If that's not right, please explain more and share screenshots & code snippets in order to help us understand.

Strange effect when resizing Control

I have created two custom controls. A rectangle and an ellipse. I'm am able to move them by dragging with the mouse, but I also want to resize them. The rectangle resizing works fine, but resizing of the ellipse gives a strange effect. When I click on the ellipse after resizing and drag it again the ellipse looks normal again. Here the link with a gif showing what I mean by a 'strange' effect http://gyazo.com/319adb7347ed20fe28b6b93ced8744eb. How fix this effect? Also the ellipse has some white space in the corners because it's drawn in a rectangle shape, maybe there's a way to fix that too?
Control.cs
class Ellipse : Control
{
Point mDown { get; set; }
public Ellipse()
{
MouseDown += shape_MouseDown;
MouseMove += shape_MouseMove;
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
// Draw a black ellipse in the rectangle represented by the control.
e.Graphics.FillEllipse(Brushes.Black, 0, 0, Width, Height);
//Set transparent background
SetStyle(ControlStyles.SupportsTransparentBackColor | ControlStyles.DoubleBuffer, true);
this.BackColor = Color.Transparent;
}
public void shape_MouseDown(object sender, MouseEventArgs e)
{
mDown = e.Location;
}
public void shape_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
Location = new Point(e.X + Left - mDown.X, e.Y + Top - mDown.Y);
}
}
/* Allow resizing at the bottom right corner */
protected override void WndProc(ref Message m)
{
const int wmNcHitTest = 0x84;
const int htBottomLeft = 16;
const int htBottomRight = 17;
if (m.Msg == wmNcHitTest)
{
int x = (int)(m.LParam.ToInt64() & 0xFFFF);
int y = (int)((m.LParam.ToInt64() & 0xFFFF0000) >> 16);
Point pt = PointToClient(new Point(x, y));
Size clientSize = ClientSize;
if (pt.X >= clientSize.Width - 16 && pt.Y >= clientSize.Height - 16 && clientSize.Height >= 16)
{
m.Result = (IntPtr)(IsMirrored ? htBottomLeft : htBottomRight);
return;
}
}
base.WndProc(ref m);
}
}
}
Form1.cs
In this way I create the Ellipse's this code is from the panel_MouseUp (object sender, MouseEventArgs e) method.
case Item.Ellipse:
var el = new Ellipse();
panel.Controls.Add(el);
el.Location = new Point(x, y);
el.Width = (xe - x);
el.Height = (ye - y);
break;

You need to tell the control to repaint itself completely when it is resized. Set its ResizeRedraw property to true. You also need to be careful what you do in the Paint event handler, it should never have global state side-effects. As written, your control promptly crashed the designer when I tried it.
Remove the last 2 lines from OnPaint and make your constructor look like this:
public Ellipse() {
MouseDown += shape_MouseDown;
MouseMove += shape_MouseMove;
SetStyle(ControlStyles.SupportsTransparentBackColor, true);
this.BackColor = Color.Transparent;
this.DoubleBuffered = true;
this.ResizeRedraw = true;
}
Further improve this by overriding OnMouseDown/Move() instead of using the events. And look at ControlPaint.DrawGrabHandle() to make the resizing a bit more intuitive.

Drawing lines behind textbox C#

I am working on creating a simple notebook application. I have been asked to make the input area look like a sheet of notebook paper, with the text sitting on light blue lines. I am trying to make this work, but it seems to be failing miserably.
So far, I have created a transparent RichTextBox that sits on top of a panel. The Text Box is:
using System;
using System.Windows.Forms;
public class TransparentTextBox : RichTextBox
{
public TransparentTextBox()
{
this.SetStyle(ControlStyles.Opaque, true);
this.SetStyle(ControlStyles.OptimizedDoubleBuffer, false);
}
protected override CreateParams CreateParams
{
get
{
CreateParams parms = base.CreateParams;
parms.ExStyle |= 0x20; // Turn on WS_EX_TRANSPARENT
return parms;
}
}
}
The paint code for the panel:
private void paper_Paint(object sender, PaintEventArgs e)
{
Graphics g = e.Graphics;
g.Clear(Color.White);
g.DrawLine(new Pen(Brushes.LightPink, 2), 20, 0, 20, paper.Height);
int h = TextRenderer.MeasureText("Testj", txtBody.Font).Height;
for (int x = 2 + h; x < paper.Height; x += h)
{
g.DrawLine(new Pen(Brushes.LightSkyBlue, 2), 0, x, paper.Width, x);
}
}
The lines are static, and they will grow to fit any font size/family that is chosen. The problem is when the text box is scrolled. The lines won't move with the text. I have tried to link the handle of the scroll bar to the lines, but they don't seem to be linking properly.
The code to get the current scroll position:
[StructLayout(LayoutKind.Sequential)]
public struct SCROLLINFO
{
public int cbSize;
public uint fMask;
public int nMin;
public int nMax;
public uint nPage;
public int nPos;
public int nTrackPos;
}
public enum ScrollBarDirection
{
SB_HORZ = 0,
SB_VERT = 1,
SB_CTL = 2,
SB_BOTH = 3
}
public enum ScrollInfoMask
{
SIF_RANGE = 0x1,
SIF_PAGE = 0x2,
SIF_POS = 0x4,
SIF_DISABLENOSCROLL = 0x8,
SIF_TRACKPOS = 0x10,
SIF_ALL = SIF_RANGE + SIF_PAGE + SIF_POS + SIF_TRACKPOS
}
...
public partial class Form1 : Form
{
[DllImport("User32.dll", EntryPoint = "GetScrollInfo")]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool GetScrollInfo([In]IntPtr hwnd, [In]int fnBar, [In, Out]ref SCROLLINFO lpsi);
...
private void txtBody_VScroll(object sender, EventArgs e)
{
inf.cbSize = Marshal.SizeOf(inf);
inf.fMask = (int)ScrollInfoMask.SIF_ALL;
GetScrollInfo(txtBody.Handle, 1, ref inf);
Console.WriteLine(inf.nTrackPos + ":" + inf.nPos + ":" + TextRenderer.MeasureText("Testj", txtBody.Font).Height);
paper.Invalidate();
}
Then the paint above was modified to use this:
for (int x = inf.nPos % h; x < paper.Height; x += h)
{
g.DrawLine(new Pen(Brushes.LightSkyBlue, 2), 0, x, paper.Width, x);
}
I also tried to use nTrackPos, but neither seemed to follow the text like I want it to. I'm not too familiar with C#, so I wanted to know what I am missing/could do better. I am using Visual Studio 2008, with Visual C# 2008. .Net framework 3.5 SP1

So, here is what I came up with after some intensive googling. I decided to follow more into Gusman's comment on my question and look into drawing on the textbox again. After some playing, I realized I was improperly calculating the position of the start line. So, I reconfigured my custom RichTextBox to look like:
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace Journal
{
class CustomRichTextBox : RichTextBox
{
private const int WM_HSCROLL = 0x114;
private const int WM_VSCROLL = 0x115;
private const int WM_MOUSEWHEEL = 0x20A;
private const int WM_PAINT = 0x00F;
private const int EM_GETSCROLLPOS = 0x4DD;
public int lineOffset = 0;
[DllImport("user32.dll")]
public static extern int SendMessage(
IntPtr hWnd,
int Msg,
IntPtr wParam,
ref Point lParam
);
protected override void WndProc(ref Message m)
{
base.WndProc(ref m);
if (m.Msg == WM_PAINT)
{
using (Graphics g = base.CreateGraphics())
{
Point p = new Point();
//get the position of the scrollbar to calculate the offset
SendMessage(this.Handle, EM_GETSCROLLPOS, IntPtr.Zero, ref p);
//draw the pink line on the side
g.DrawLine(new Pen(Brushes.LightPink, 2), 0, 0, 0, this.Height);
//determine how tall the text will be per line
int h = TextRenderer.MeasureText("Testj", this.Font).Height;
//calculate where the lines need to start
lineOffset = h - (p.Y % h);
//draw lines until there is no more box
for (int x = lineOffset; x < Height; x += h)
{
g.DrawLine(new Pen(Brushes.LightSkyBlue, 2), 0, x, Width, x);
}
//force the panel under us to draw itself.
Parent.Invalidate();
}
}
}
public CustomRichTextBox()
{
this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
}
}
}
I then set this box inside of a panel to get the padding I want. The panel is forced to redraw itself with the text box.

c# : how to remove tabcontrol border?

In my form, I'm using a tabcontrol. I want to hide the tab headers and border both. I can do either one, if I try to hide the headers then the border becomes visible. Can anyone help me, please? thanks and here's my code:
public Form3()
{
InitializeComponent();
this.NativeTabControl1 = new NativeTabControl();
this.NativeTabControl1.AssignHandle(this.tabControl1.Handle);
}
private NativeTabControl NativeTabControl1;
private class NativeTabControl : NativeWindow
{
protected override void WndProc(ref Message m)
{
if ((m.Msg == TCM_ADJUSTRECT))
{
RECT rc = (RECT)m.GetLParam(typeof(RECT));
//Adjust these values to suit, dependant upon Appearance
rc.Left -= 3;
rc.Right += 3;
rc.Top -= 3;
rc.Bottom += 3;
Marshal.StructureToPtr(rc, m.LParam, true);
}
base.WndProc(ref m);
}
private const Int32 TCM_FIRST = 0x1300;
private const Int32 TCM_ADJUSTRECT = (TCM_FIRST + 40);
private struct RECT
{
public Int32 Left;
public Int32 Top;
public Int32 Right;
public Int32 Bottom;
}
private void Form3_Load(object sender, EventArgs e)
{
//hides tabcontrol headers
tabControl1.Appearance = TabAppearance.Buttons;
tabControl1.ItemSize = new Size(0, 1);
tabControl1.SizeMode = TabSizeMode.Fixed;
}
}

There is another thread on Stackoverflow, which provides some ideas to hide the tab row of the TabControl in Windows Forms.
My favorite one is to override WndProc and set the Multiline property to true.
public partial class TabControlWithoutHeader : TabControl
{
public TabControlWithoutHeader()
{
if (!this.DesignMode) this.Multiline = true;
}
protected override void WndProc(ref Message m)
{
if (m.Msg == 0x1328 && !this.DesignMode)
m.Result = new IntPtr(1);
else
base.WndProc(ref m);
}
}
I tested the code on Windows 8.1 and see neither the tabs nor a border line. So I think you do not need to use code like you posted.

I would usually suggest doing this in the xaml not C# (I'm a WPF developer) I believe you can do it in the C# as well by naming both the TabControl as well as each Tab itself.
tabControlName.BorderBrush = null;
///^Gets rid of the TabControl's border.
tabName1.Height = 0;
tabName2.Height = 0;
tabNameETC.Height = 0;
///^Removes the tabs(headers) if you have the TabControl.TabStripPlacement set to left
/// or right, then use the following instead:
tabName1.Width = 0
tabName2.Width = 0
tabNameETC.Width = 0

Transparent window layer that is click-through and always stays on top

This is some code that I picked up which I tried to implement. Its purpose is to create a form layer which is transparent, full screen, borderless, clickthrough, and always on top of other windows. It then lets you draw using directx over the top of it remaining otherwise transparent.
The parts that don't work are the click-through part, and the directx render. When I run it I basically have an invisible force field in front of all other windows and have to alt-tab around to visual studio to quickly press ALT F5 and end the debug (so at least the always on top and transparency works). I have been trying to figure out why those parts don't work, but my newbie c# skills fail me. hopefully someone can spot why and provide a modification.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Globalization;
using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;
using System.Threading;
namespace MinimapSpy
{
public partial class Form1 : Form
{
private Margins marg;
//this is used to specify the boundaries of the transparent area
internal struct Margins
{
public int Left, Right, Top, Bottom;
}
[DllImport("user32.dll", SetLastError = true)]
private static extern UInt32 GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
[DllImport("user32.dll")]
static extern bool SetLayeredWindowAttributes(IntPtr hwnd, uint crKey, byte bAlpha, uint dwFlags);
public const int GWL_EXSTYLE = -20;
public const int WS_EX_LAYERED = 0x80000;
public const int WS_EX_TRANSPARENT = 0x20;
public const int LWA_ALPHA = 0x2;
public const int LWA_COLORKEY = 0x1;
[DllImport("dwmapi.dll")]
static extern void DwmExtendFrameIntoClientArea(IntPtr hWnd, ref Margins pMargins);
private Device device = null;
public Form1()
{
//Make the window's border completely transparant
SetWindowLong(this.Handle, GWL_EXSTYLE,
(IntPtr)(GetWindowLong(this.Handle, GWL_EXSTYLE) ^ WS_EX_LAYERED ^ WS_EX_TRANSPARENT));
//Set the Alpha on the Whole Window to 255 (solid)
SetLayeredWindowAttributes(this.Handle, 0, 255, LWA_ALPHA);
//Init DirectX
//This initializes the DirectX device. It needs to be done once.
//The alpha channel in the backbuffer is critical.
PresentParameters presentParameters = new PresentParameters();
presentParameters.Windowed = true;
presentParameters.SwapEffect = SwapEffect.Discard;
presentParameters.BackBufferFormat = Format.A8R8G8B8;
this.device = new Device(0, DeviceType.Hardware, this.Handle,
CreateFlags.HardwareVertexProcessing, presentParameters);
Thread dx = new Thread(new ThreadStart(this.dxThread));
dx.IsBackground = true;
dx.Start();
InitializeComponent();
}
protected override void OnPaint(PaintEventArgs e)
{
//Create a margin (the whole form)
marg.Left = 0;
marg.Top = 0;
marg.Right = this.Width;
marg.Bottom = this.Height;
//Expand the Aero Glass Effect Border to the WHOLE form.
// since we have already had the border invisible we now
// have a completely invisible window - apart from the DirectX
// renders NOT in black.
DwmExtendFrameIntoClientArea(this.Handle, ref marg);
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void dxThread()
{
while (true)
{
//Place your update logic here
device.Clear(ClearFlags.Target, Color.FromArgb(0, 0, 0, 0), 1.0f, 0);
device.RenderState.ZBufferEnable = false;
device.RenderState.Lighting = false;
device.RenderState.CullMode = Cull.None;
device.Transform.Projection = Matrix.OrthoOffCenterLH(0, this.Width, this.Height, 0, 0, 1);
device.BeginScene();
//Place your rendering logic here
device.EndScene();
//device.Present();
}
this.device.Dispose();
Application.Exit();
}
}

Here's a refined full sample code for making a window topmost - click through - transparent (= alpha blended). The sample makes a rotating color wheel which is rendered with DirectX, or actually with XNA 4.0, because I believe Microsoft has discontinued developing the managed directx and favours XNA today.
using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using Microsoft.Xna.Framework.Graphics;
namespace ClickThroughXNA
{
public partial class Form1 : Form
{
// Directx graphics device
GraphicsDevice dev = null;
BasicEffect effect = null;
// Wheel vertexes
VertexPositionColor[] v = new VertexPositionColor[100];
// Wheel rotation
float rot = 0;
public Form1()
{
InitializeComponent();
StartPosition = FormStartPosition.CenterScreen;
Size = new System.Drawing.Size(500, 500);
FormBorderStyle = System.Windows.Forms.FormBorderStyle.None; // no borders
TopMost = true; // make the form always on top
Visible = true; // Important! if this isn't set, then the form is not shown at all
// Set the form click-through
int initialStyle = GetWindowLong(this.Handle, -20);
SetWindowLong(this.Handle, -20, initialStyle | 0x80000 | 0x20);
// Create device presentation parameters
PresentationParameters p = new PresentationParameters();
p.IsFullScreen = false;
p.DeviceWindowHandle = this.Handle;
p.BackBufferFormat = SurfaceFormat.Vector4;
p.PresentationInterval = PresentInterval.One;
// Create XNA graphics device
dev = new GraphicsDevice(GraphicsAdapter.DefaultAdapter, GraphicsProfile.Reach, p);
// Init basic effect
effect = new BasicEffect(dev);
// Extend aero glass style on form init
OnResize(null);
}
protected override void OnResize(EventArgs e)
{
int[] margins = new int[] { 0, 0, Width, Height };
// Extend aero glass style to whole form
DwmExtendFrameIntoClientArea(this.Handle, ref margins);
}
protected override void OnPaintBackground(PaintEventArgs e)
{
// do nothing here to stop window normal background painting
}
protected override void OnPaint(PaintEventArgs e)
{
// Clear device with fully transparent black
dev.Clear(new Microsoft.Xna.Framework.Color(0, 0, 0, 0.0f));
// Rotate wheel a bit
rot+=0.1f;
// Make the wheel vertexes and colors for vertexes
for (int i = 0; i < v.Length; i++)
{
if (i % 3 == 1)
v[i].Position = new Microsoft.Xna.Framework.Vector3((float)Math.Sin((i + rot) * (Math.PI * 2f / (float)v.Length)), (float)Math.Cos((i + rot) * (Math.PI * 2f / (float)v.Length)), 0);
else if (i % 3 == 2)
v[i].Position = new Microsoft.Xna.Framework.Vector3((float)Math.Sin((i + 2 + rot) * (Math.PI * 2f / (float)v.Length)), (float)Math.Cos((i + 2 + rot) * (Math.PI * 2f / (float)v.Length)), 0);
v[i].Color = new Microsoft.Xna.Framework.Color(1 - (i / (float)v.Length), i / (float)v.Length, 0, i / (float)v.Length);
}
// Enable position colored vertex rendering
effect.VertexColorEnabled = true;
foreach (EffectPass pass in effect.CurrentTechnique.Passes) pass.Apply();
// Draw the primitives (the wheel)
dev.DrawUserPrimitives(PrimitiveType.TriangleList, v, 0, v.Length / 3, VertexPositionColor.VertexDeclaration);
// Present the device contents into form
dev.Present();
// Redraw immediatily
Invalidate();
}
[DllImport("user32.dll", SetLastError = true)]
static extern int GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
[DllImport("dwmapi.dll")]
static extern void DwmExtendFrameIntoClientArea(IntPtr hWnd, ref int[] pMargins);
}
}

A little extension/modification to Jaska's code, which the form is transparent
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.TopMost = true; // make the form always on top
this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None; // hidden border
this.WindowState = FormWindowState.Maximized; // maximized
this.MinimizeBox = this.MaximizeBox = false; // not allowed to be minimized
this.MinimumSize = this.MaximumSize = this.Size; // not allowed to be resized
this.TransparencyKey = this.BackColor = Color.Red; // the color key to transparent, choose a color that you don't use
}
protected override CreateParams CreateParams
{
get
{
CreateParams cp = base.CreateParams;
// Set the form click-through
cp.ExStyle |= 0x80000 /* WS_EX_LAYERED */ | 0x20 /* WS_EX_TRANSPARENT */;
return cp;
}
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
// draw what you want
e.Graphics.FillEllipse(Brushes.Blue, 30, 30, 100, 100);
}
}

Change your extended window style to only WS_EX_LAYERED, window style to only WS_POPUP (NO WS_SIZEBOX) and make sure to use DwmExtendFrameIntoClientArea with all -1's and this will produce transparent windows with layered support: downside is you need to bltbit with GDI from an offscreen directx rendering. Not optimal but it works. This gives mouse click throughs + directx rendering + transparency. Downside is you'll need to inform GDI anytime, pull the directx buffer (all of it or just the damaged portions) and write them to the screem with bltbit.
Setting the extended window style to WS_EX_COMPOSITED and DwmExtendedFrameIntoClientArea with all -1's (similar as above, WS_POPUP on the regular window style). This you can run directx from but no mouse clickthroughs. You can at this point define irregular paths for the hit mask and pass it to windows, its not perfect but if you know a general (non regular) area that can pass-through it'll work.
Still trying to find a true way of using opengl/directx on mac or windows platforms that can pass through mouse clicks with out having to do a bitblt to a legacy rendering system.

I have a simple way use TransparentKey property and a 1x1 pixel label with the color of Form TransparentKey.
On Form and all control MouseMouse event. Set label position to Mouse location.
private void MoveHole()
{
var newLocation = PointToClient(MousePosition);
lblHole.Location = newLocation;
}