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C# WinForms: Make panel scrollbar invisible

I have a panel1 with AutoScroll = true.I have to make panel1 scroll with btnUp and btnDown. So far I've made what I was asked for
private void btnUpClicked(Object sender, EventArgs e)
{
if (panel1.VerticalScroll.Value - 55 > 0)
panel1.VerticalScroll.Value -= 55;
else panel1.VerticalScroll.Value = 0;
}
private void btnDownClicked(Object sender, EventArgs e)
{
panel1.VerticalScroll.Value += 55;
}
But now I need to hide Scrollbar or make it invisible. I tried
panel1.VerticalScroll.Visible = false;
but it doesn't work. Any ideas guys?

Ok, I've done the working example of this for you. All you have to do is to change the max value depending on the total size of all the items inside your panel.
Form code:
public partial class Form1 : Form
{
private int location = 0;
public Form1()
{
InitializeComponent();
// Set position on top of your panel
pnlPanel.AutoScrollPosition = new Point(0, 0);
// Set maximum position of your panel beyond the point your panel items reach.
// You'll have to change this size depending on the total size of items for your case.
pnlPanel.VerticalScroll.Maximum = 280;
}
private void btnUp_Click(object sender, EventArgs e)
{
if (location - 20 > 0)
{
location -= 20;
pnlPanel.VerticalScroll.Value = location;
}
else
{
// If scroll position is below 0 set the position to 0 (MIN)
location = 0;
pnlPanel.AutoScrollPosition = new Point(0, location);
}
}
private void btnDown_Click(object sender, EventArgs e)
{
if (location + 20 < pnlPanel.VerticalScroll.Maximum)
{
location += 20;
pnlPanel.VerticalScroll.Value = location;
}
else
{
// If scroll position is above 280 set the position to 280 (MAX)
location = pnlPanel.VerticalScroll.Maximum;
pnlPanel.AutoScrollPosition = new Point(0, location);
}
}
}
Picture example:
You have to set AutoScroll option to False on your panel. I hope you understand what I've done and will get your panel running the way you want. Feel free to ask if you have any questions.

The Panel control takes on the duty you gave it by setting AutoScroll to true pretty serious. This always includes displaying the scrollbar gadget if it is necessary. So what you tried cannot work, hiding the vertical scrollbar forces Panel to recalculate layout since doing so altered the client area. It will of course discover that the scrollbar is required and promptly make it visible again.
The code that does this, Panel inherits it from ScrollableControl, is internal and cannot be overridden. This was intentional.
So using AutoScroll isn't going to get you anywhere. As an alternative, do keep in mind what you really want to accomplish. You simply want to move controls up and down. Easy to do, just change their Location property. That in turn is easiest to do if you put the controls on another panel, big enough to contain them. Set its AutoSize property to True. And implement you buttons' Click event handlers by simply changing that panel's Location property:
private const int ScrollIncrement = 10;
private void ScrollUpButton_Click(object sender, EventArgs e) {
int limit = 0;
panel2.Location = new Point(0,
Math.Min(limit, panel2.Location.Y + ScrollIncrement));
}
private void ScrollDownButton_Click(object sender, EventArgs e) {
int limit = panel1.ClientSize.Height - panel2.Height;
panel2.Location = new Point(0,
Math.Max(limit, panel2.Location.Y - ScrollIncrement));
}
Where panel1 is the outer panel and panel2 is the inner one that contains the controls. Be careful when you use the designer to put controls on it, it has a knack for giving them the wrong Parent. Be sure to use the View + Other Windows + Document Layout helper window so you can see this going wrong. After you filled it, set its AutoSizeMode property to GrowAndShrink so it snaps to its minimum size.

Try this:
panel.AutoScroll = true;
panel.VerticalScroll.Enabled = false;
panel.VerticalScroll.Visible = false;
Edit:
Actually when AutoScroll = true; It will take care of hscroll and vscroll automatically and you wont be able to change it. I found this on Panel.AutoScroll Property on MSDN
AutoScroll maintains the visibility of the scrollbars automatically. Therefore, setting the HScroll or VScroll property to true has no effect when AutoScroll is enabled.
You may try this to workaround this problem, I have copied it from this Link.
Behavior Observations 1:
If AutoScroll is set to true, you can't modify anything in VerticalScroll or HorizontalScroll. AutoScroll means AutoScroll; the control decides when scrollbars are visible, what the min/max is, etc. and you can't change a thing.
So if you want to customize the scrolling (e.g. hide scrollbars), you must set AutoScroll to false.
Looking at the source code for the ScrollableControl with Lutz Roeder's .NET Reflecter, you can see that if AutoScroll is set to true, it ignores your attempts to change property values within the VerticalScroll or HorizontalScroll properties such as MinValue, MaxValue, Visible etc.
Behavior Observations 2:
With AutoScroll set to false, you can change VerticalScroll.Minimum, VerticalScroll.Maximum, VerticalScroll.Visible values.
However, you cannot change VerticalScroll.Value!!! Wtf! If you set it to a non-zero value, it resets itself to zero.
Instead, you must set AutoScrollPosition = new Point( 0, desired_vertical_scroll_value );
And finally, SURPRISE, when you assign positive values, it flips them to negative values, so if you check AutoScrollPosition.X, it will be negative! Assign it positive, it comes back negative.
So yeah, if you want custom scrolling, set AutoScroll to false. Then set the VerticalScroll and HorizontalScroll properties (except Value). Then to change the scroll value, you need to set AutoScrollPosition, even though you aren't using auto scrolling! Finally, when you set the AutoScrollPosition, it will take on the opposite (i.e. negative) value that you assign to it, so if you want to retrieve the current AutoScrollPosition later, for example if you want to offset the scroll value by dragging the mouse to pan, then you need to remember to negate the value returned by AutoScrollPosition before reassigning it to AutoScrollPosition with some offset. WOW. Wtf.
One other thing, if you are trying to pan with the mouse, use the values of Cursor.Position rather than any mouse locations returned by the mouse events parameters. Scrolling the control will cause the event parameter values to be offset as well, which will cause it to start firing mouse move events complete with undesired values. Just use Cursor.Position, because it will use mouse screen coordinates as a fixed frame of reference, which is what you want when you're trying to pan/offset the scroll value.

PictureBox image does not shrink, but PictureBox itself expand to fit the image

When I add a picturebox to the form at runtime, the picturebox acts exactly like I want. But when I add it to the panel, the pictureBox expands to fit the image.
Below is the code:
private PictureBox globalPicBox = (PictureBox)null;
private void Form1_Load(object sender, EventArgs e)
{
this.globalPicBox = new PictureBox();
this.globalPicBox.Name = "a";
this.globalPicBox.Tag = (object)"a";
this.globalPicBox.SizeMode = PictureBoxSizeMode.StretchImage;
this.globalPicBox.Top = 50;
this.globalPicBox.Left = 50;
this.globalPicBox.Height = 100;
this.globalPicBox.Width = 100;
this.globalPicBox.Image = Image.FromFile(#"C:\Users\PC\Downloads\Photo.jpg");
this.globalPicBox.BorderStyle = BorderStyle.FixedSingle;
this.globalPicBox.AutoSize = true;
this.panel1.Controls.Add((Control)this.globalPicBox);
}
What is the problem? And why?

Based on your edit ... set globalPicBox.AutoSize = false and it'll work.
If it doesn't please check the rest of your code for changes to globalPicBox's AutoSize, SizeMode and Dock parameters and hopefully you'll find your answer!

Simple Just Set globalPicBox.SizeMode=Strech
The image will shrink or stretch to meet the picturebox size and your picture box will not expand or shrink it will remain the same size

How to add scrollbar to groupbox? C# 4.0

So... did someone know how to make it?...
In a panel is easy, because we can set the "AutoScroll" property, to true... but groupbox doesn't have it.
Anyways... exists some way for it?, thanks in advance ;-).

Quite simple... Add a panel inside a group box.

Declare Group box object and Panel object which will contain the scroll bar by default and some of my Check box objects;I read somewhere that Group box's don't have scroll bar for aesthetic reasons(i hope it's not true, why not let the user make that call). Solution is simple, once you know that you will create a panel that will lay on top of your group box just to get your scroll bar.
private System.Windows.Forms.GroupBox grpDR;//GROUPBOX IN WHICH PANEL WILL OVERLAY
private System.Windows.Forms.Panel grpScrlDR;//PANEL WHICH WILL HAVE SCROLL BAR AND CONTAIN CHECK BOXES
private System.Windows.Forms.CheckBox chkDr2;
private System.Windows.Forms.CheckBox chkDr1;
private void InitializeComponent()
{
this.grpScrlDR = new System.Windows.Forms.Panel();
this.chkDr2 = new System.Windows.Forms.CheckBox();
this.chkDr1 = new System.Windows.Forms.CheckBox();
this.grpDR = new System.Windows.Forms.GroupBox();
this.grpScrlDR.SuspendLayout();
this.grpDR.SuspendLayout();
//
// grpScrlDR
// PANEL DETAILS ADDING CHECKBOX CONTROLS AND ENABLING AUTO SCROLL
this.grpScrlDR.AutoScroll = true;
this.grpScrlDR.Controls.Add(this.chkDr2);
this.grpScrlDR.Controls.Add(this.chkDr1);
this.grpScrlDR.Dock = System.Windows.Forms.DockStyle.Fill;
this.grpScrlDR.Location = new System.Drawing.Point(5, 336);
this.grpScrlDR.Name = "grpScrlDR";
this.grpScrlDR.Size = new System.Drawing.Size(175, 230);
this.grpScrlDR.TabIndex = 0;
//
// chkDr2
//
this.chkDr2.AutoSize = true;`
this.chkDr2.Location = new System.Drawing.Point(13, 45);
this.chkDr2.Name = "chkDr2";
this.chkDr2.Size = new System.Drawing.Size(54, 20);
this.chkDr2.TabIndex = 1;
this.chkDr2.Text = "Permit#";
this.chkDr2.UseVisualStyleBackColor = true;
this.chkDr2.CheckedChanged += new System.EventHandler(this.chkDr_CheckedChanged);
//
// chkDr1
//
this.chkDr1.AutoSize = true;
this.chkDr1.Checked = true;
this.chkDr1.CheckState = System.Windows.Forms.CheckState.Checked;
this.chkDr1.Location = new System.Drawing.Point(13, 22);
this.chkDr1.Name = "chkDr1";
this.chkDr1.Size = new System.Drawing.Size(54, 20);
this.chkDr1.TabIndex = 0;
this.chkDr1.Text = "Account";
this.chkDr1.UseVisualStyleBackColor = true;
this.chkDr1.CheckedChanged += new System.EventHandler(this.chkDr_CheckedChanged);
//
// grpDR
// GROUP BOX DETAILS - GROUP BOX IS ADDING PANEL CONTROLS
this.grpDR.Controls.Add(this.grpScrlDR);
this.grpDR.Font = new System.Drawing.Font("Microsoft Sans Serif", 9.75F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
this.grpDR.Location = new System.Drawing.Point(5, 336);
this.grpDR.Name = "grpDR";
this.grpDR.Size = new System.Drawing.Size(175, 230);
this.grpDR.TabIndex = 46;
this.grpDR.TabStop = false;
this.grpDR.Text = "Report by";
this.grpDR.Visible = false;
}

The GroupBox cannot display a scroll bar. If you need a control similar to a GroupBox that can contain a scroll bar, see the Panel control
Read This Article - Find (The GroupBox cannot display a scroll bar) Text

If you need to add a panel inside of your GroupBox, Dock a Panel inside of the GroupBox and set the AutoScroll property on the docked Panel to true. You can then place any controls you need inside of the GroupBox on the Panel, which will scroll when necessary.
If you don't like the way that looks as you stated above, then you have two possible options:
There may be a way to hack (more like "abuse" in this situation) the GroupBox control by making calls into the native Win32 API to add a scrollbar. I rarely use native calls on managed controls, but I've done this in situations where, for instance, I need to disable the scroll bar on a ListView as ListView doesn't expose this property. Below I expose the native Win32 function for use in C#, just call SetScrollBarVisible to enable or disable the scrollbar as needed from your code (I have not tested this on a GroupBox):
If aesthetics is THAT important to you (not a bad thing, user experience is greatly underappreciated in many areas of the application development world) and adding a scroll bar to the GroupBox doesn't work/look good to you, you will need to find another solution. I would imagine the best solution would be to make your own control from the ground up that meets your expectations (or modify the scrollbar itself, no idea how to do this), though this is can be a lot more work than it might be worth.
Here is how I expose and call the Win32 function SetScrollBar from my C# code (sorry, the DllImport won't format as a code block for some reason):
[DllImport ("user32")]
private static extern long ShowScrollBar (long hwnd , long wBar, long bShow);
long SB_HORZ = 0;
long SB_VERT = 1;
long SB_BOTH = 3;
private static void SetScrollBarVisible (Control control, long sb, bool enable)
{
if (control != null) return;
if (enable)
ShowScrollBar(control.Handle.ToInt64(), sb, 1);
else
ShowScrollBar(control.Handle.ToInt64(), sb, 0);
}

To do this you would have to add 1 panel to the groupbox and set the autoscroll property to true.
Then you would add a second panel which would be large then the first panel.
On this second panel (StringPanel in the beleow code) you would add controls.
System.Windows.Forms.GroupBox StringsGroup;
System.Windows.Forms.Panel StingPanel;
System.Windows.Forms.Panel StringPanel2;
StringsGroup = new System.Windows.Forms.GroupBox();
StingPanel = new System.Windows.Forms.Panel();
StringPanel2 = new System.Windows.Forms.Panel();
//Add your controls to StringPanel
StingPanel.Size = new System.Drawing.Size(300, 800);
StringPanel2.Size = new System.Drawing.Size(325, 345);
StringPanel2.AutoScroll = true;
this.StringPanel2.Controls.Add(StingPanel);
this.StringsGroup.Controls.Add(this.StringPanel2);

Horizontal Scroll Bar Tip
If you have a panel where all the controls contained within it are anchored to the top (so that they are centered) you will never see the horizontal scroll bar. You need to have at least one control that is anchored left & top that disappears when the panel is too small to show it in order for the horizontal scroll bar to appear. I put a label with hidden text on the panel to accomplish this.
This little tidbit took me quite a while to discover! Hope it's helpful!

If you dont want scrollbars, but want your GroupBox to grow, you can edit these below properties from the Layout section as shown below.
AutoSize = true;
AutoSizeMode = GrowOnly;

Winforms, creating padding when using Dock properties

How do I add padding, or some space between the textboxes when using dockstyle.top property?
for(int i =0; i< 10; i++) {
textboxes[i] = new TextBox();
textboxes[i].Dock = DockStyle.Top;
mypanel.Controls.Add(textboxes[i]);
}
The code above puts textboxes right beneath each other. Can't figure this out without using mass panels or fixed positioning. How to do the following?
1) I would like to add around 10-20pixels between boxes.
2) How to change size (height,width) of the textboxes, since when using dockstyle.top it ignores the size commands ?

With DockStype.Top you can't change the width of your TextBoxes, cause they are docked. You can only change the height. But to change the height of a TextBox you have to set the Multiline = true beforehand.
To get the space between the different boxes you have to put each TextBox within a panel, set the TextBox.Dock = Fill, the Panel.Dock = Top and the Panel.Padding = 10. Now you have some space between each TextBox.
Sample Code
for (int i = 0; i < 10; i++)
{
var panelTextBox = CreateBorderedTextBox();
this.Controls.Add(panelTextBox);
}
private Panel CreateBorderedTextBox()
{
var panel = CreatePanel();
var textBox = CreateTextBox();
panel.Controls.Add(textBox);
return panel;
}
private Panel CreatePanel()
{
var panel = new Panel();
panel.Dock = DockStyle.Top;
panel.Padding = new Padding(5);
return panel;
}
private TextBox CreateTextBox()
{
var textBox = new TextBox();
textBox.Multiline = true;
textBox.Dock = DockStyle.Fill;
return textBox;
}
What i forgot, you can also give a try to the FlowLayoutPanel. Just remove the DockStyle.Top from the panels and put them into the FlowLayoutPanel. Also you should set the FlowDirection to TopDown. Maybe this can also help you to solve your problem, too.

Another work around that suits smaller layouts is to just add a Label control afterwards also docked to the Top, which is not AutoSized, Text=" ", Height=your padding. This is quite useful for the odd bit of padding when using the designer.

I know where you're coming from, this is especially frustrating after returning to WinForms from WPF.
I would suggest using a TableLayoutPanel, in which each TextBox would get its own cell, and adjusting the properties of the cells. This should solve both your padding and size problems.
Another alternative would be to use some more complex layout controls, such as the DevExpress ones (not free).

How to make a ToolStripComboBox to fill all the space available on a ToolStrip?

A ToolStripComboBox is placed after a ToolStripButton and is folowed by another one, which is right-aligned. How do I best set up the ToolStripComboBox to always adjust its length to fill all the space available between the preceeding and the folowing ToolStripButtons?
In past I used to handle a parent resize event, calculate the new length to set based on neighboring elements coordinates and setting the new size. But now, as I am developing a new application, I wonder if there is no better way.

I use the following with great success:
private void toolStrip1_Layout(System.Object sender, System.Windows.Forms.LayoutEventArgs e)
{
int width = toolStrip1.DisplayRectangle.Width;
foreach (ToolStripItem tsi in toolStrip1.Items) {
if (!(tsi == toolStripComboBox1)) {
width -= tsi.Width;
width -= tsi.Margin.Horizontal;
}
}
toolStripComboBox1.Width = Math.Max(0, width - toolStripComboBox1.Margin.Horizontal);
}
The above code does not suffer from the disapearing control problem.

There's no automatic layout option for this. But you can easily do it by implementing the ToolStrip.Resize event. This worked well:
private void toolStrip1_Resize(object sender, EventArgs e) {
toolStripComboBox1.Width = toolStripComboBox2.Bounds.Left - toolStripButton1.Bounds.Right - 4;
}
protected override void OnLoad(EventArgs e) {
toolStrip1_Resize(this, e);
}
Be sure to set the TSCB's AutoResize property to False or it won't work.

ToolStrip ts = new ToolStrip();
ToolStripComboBox comboBox = new TooLStripComboBox();
comboBox.Dock = DockStyle.Fill;
ts.LayoutStyle = ToolStripLayoutStyle.Table;
((TableLayoutSettings)ts.LayoutSettings).ColumnCount = 1;
((TableLayoutSettings)ts.LayoutSettings).RowCount = 1;
((TableLayoutSettings)ts.LayoutSettings).SetColumnSpan(comboBox,1);
ts.Items.Add(comboBox);
Now the combobox will dock fill correctly. Set Column or Row span accordingly.