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How to get a Label with AutoSize to update its Position while anchored to the Right?

I have a simple System.Windows.Forms.Label in a System.Windows.Forms.Form.
I want to dynamically resize the label to fit text loaded runtime, while keeping it Anchored to the right and bottom of its parent form.
According to the MSDN Documentation:
It is “always true” that the Location Property remains constant (i.e., that the top left position of the Control will never change).
It is “always true” that the Anchor property is respected when AutoSize is true (i.e., that the Location Property—the top-left corner—will be modified so that the Anchored Sides maintain their initial distance from the edges of their parent controls).
From my reading of this, I would expect that the second truth overrides the first when Anchor is anything but AnchorStyles.None.
However, this doesn't seem to bear out in practice.
Consider the following:
// From ExampleForm.Designer.cs
this.label = new System.Drawing.Label();
this.label.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
this.label.AutoSize = true;
this.label.Location = new System.Drawing.Point(600, 400);
this.label.Size = new System.Drawing.Size(170, 20);
this.label.Text = "[Populated at Runtime]";
this.label.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
// ...
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(800, 450);
this.Controls.Add(this.label);
// ...
// Sometime after Form Initialization, this is called
void PopulateLabel() {
var oldRight = label.Right;
label.Text = "Hey here's some new text. It's pretty long so the control will have to resize";
// Without this next line, the Right Anchor distance is not maintained.
// label.Left -= (label.Right - oldRight);
System.Diagnostics.Debug.Assert(label.Anchor.HasFlag(AnchorStyles.Right) && label.Right == oldRight, "The label didn't stay anchored to the right");
}
Obviously I can work around this by tracking the distance manually, as above.
I just wonder if there isn't some way this is “supposed” to work that I'm doing wrong.
The one observation I have to offer is this: it works if the label is not anchored to the bottom.
Do I need to call Suspend/Resume/PerformLayout on the Label? on the Form?
Are the docs wrong?
Am I being foolishly naïve or completely misunderstanding something?
Do I need some sort of intermediary Control for this to work and the docs assume I know this?
To address some possible complications that show up in similar questions (or that I dreamt up):
rightToLeft is false,
Dock is DockStyle.None,
the label's Parent is the form itself, not an intermediary panel or other control.
the Margin seems irrelevant
Anchoring to the Top or Bottom seems irrelevant to Right not working.
System.Windows.Form.Button works as expected. I haven't tested other controls.

Try using a TableLayout, it tends to obey the Control layout properties better. E.g:
public class MyForm : Form {
Label label = new Label() { BackColor = Color.Blue, ForeColor = Color.White };
public MyForm() {
TableLayoutPanel panel = new TableLayoutPanel() { BackColor = Color.Green };
panel.ColumnCount = 1;
panel.RowCount = 1;
panel.Controls.Add(label, 0, 0);
panel.Dock = DockStyle.Bottom;
panel.AutoSize = true;
panel.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
panel.Controls.Add(label);
//this.label.Anchor = AnchorStyles.Right | AnchorStyles.Top;// | AnchorStyles.Bottom; // ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
//this.label.Dock = DockStyle.Fill;
this.label.Dock = DockStyle.Right;
this.label.AutoSize = true;
this.label.Margin = Padding.Empty;
//this.label.Location = new System.Drawing.Point(600, 400);
//this.label.Size = new System.Drawing.Size(170, 20);
this.label.Text = "[Populated at Runtime]";
//this.label.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
// ...
//this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
//this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(800, 450);
//this.Controls.Add(this.label);
this.Controls.Add(panel);
// ...
Button btn = new Button { Text = "Change text" };
btn.Click += delegate {
PopulateLabel();
};
Controls.Add(btn);
}
// Sometime after Form Initialization, this is called
void PopulateLabel() {
var oldRight = label.Right;
label.Text = "Hey here's some new text. It's pretty long so the control will have to resize";
// Without this next line, the Right Anchor distance is not maintained.
// label.Left -= (label.Right - oldRight);
//System.Diagnostics.Debug.Assert(label.Anchor.HasFlag(AnchorStyles.Right) && label.Right == oldRight, "The label didn't stay anchored to the right");
}
}

Custom scrollbar scrolling triggers AutoScroll scrollbars

I've been using a UserControl to display a list of controls. I initially had AutoScroll enabled, and then opted to not using it. I chose against using it as it stood out and simply didn't 'look' good with the controls theme I've been using.
I took a shot at a framework called MetroFramework, and I've opted to use the MetroScrollBar scrollbar control for a vertical scrollbar.
I've fully disabled AutoScroll, and I then decided to implement the Scrollbar. I simply did this by:
scbMain.Scroll += (sender, e) => { VerticalScroll.Value = scbMain.Value; };
(where scbMain is the Scrollbar I'm discussing)
This works, but not as expected. As soon as I scroll, I get a crazy flickering effect from the default scrollbar, as shown here. A longer list has the same effect, but more pronounced.
I've attempted to hide the existing scrollbars:
VerticalScroll.Visible = false;
HorizontalScroll.Visible = false;
VerticalScroll.Enabled = false;
HorizontalScroll.Enabled = false;
This has had no effect on fixing my issue.
It should be noted: My scrollbar is docked to the right and there're no other container controls within the UserControl.

Ok. Problem solved. The issue was in this line of code:
scbMain.Scroll += (sender, e) => { ----> /*(Here*/ VerticalScroll.Value = scbMain.Value; <---- };
You are actully setting the scroll value of your user control, basically you tell the system to invoke the autoscroll property to set the value!
The correct way is to NOT autoscroll the user control but to scroll a container inside eg a panel. So add a panel to your user control. You are going to scroll the panel and all the controls inside it (in this example i will add the button).
this.btnExample.Location = new System.Drawing.Point(62, 0);
this.btnExample.Name = "btnExample";
this.btnExample.Size = new System.Drawing.Size(75, 390);
this.btnExample.TabIndex = 1;
this.btnExample.Text = "Out of Bounds";
this.btnExample.UseVisualStyleBackColor = true;
this.panel1.Controls.Add(this.btnExample);
this.panel1.Location = new System.Drawing.Point(0, 0);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(270, 391); //the width must fit inside your user control and the height was arbitrary
this.panel1.TabIndex = 2;
this.Controls.Add(this.panel1);
this.Controls.Add(this.scbMain);
this.Name = "CtrlScroll";
this.Size = new System.Drawing.Size(474, 300);
The scrolling:
public CtrlScroll() {
InitializeComponent();
scbMain.Scroll += ( sender, e ) => {
//Normally the if statement whouldn't be needed but the metro srollbar
//has a weird behaviour when the scroll value becomes max
if( scbMain.Value > panel1.Height - this.Height ) {
panel1.Top = -( panel1.Height - this.Height );
}
else {
panel1.Top = -scbMain.Value;
};
};
int maxVertical = panel1.Height;
// SmallChange is typically 1%.
int smallChangeVertical = Math.Max( (int)( maxVertical / 100 ), 1 );
// LargeChange is one page.
int largeChangeVertical = this.Height;
scbMain.Minimum = 0;
scbMain.Maximum = maxVertical;
scbMain.SmallChange = smallChangeVertical;
scbMain.LargeChange = largeChangeVertical;
}

How do you make AutoSize happen immediately?

The problem
I'm dynamically adding Buttons to the WinForm. As I do so, I'm repositioning existing Buttons to prevent overlap. The AutoSize property is being used to automatically set Width.
For longer text (that pushes Buttons beyond their default Width), the below code doesn't work.
For example:
b.Width is 75 before AutoSize is set
b.Width is 75 after AutoSize is set
When shifting other Buttons, it shifts them by b.Width + buffer = 83
However after addButton()completes, the AutoSize kicks in and sets the width to 150, overlapping the next Button which is only 83 pixels away instead of 158.
AutoSize appears to change the size of the control too late for it to be of use. How can I make it happen immediately?
Attempt 1 - Code
public void addButton(string text)
{
const int buffer = 8;
//Construct new button
Button b = new Button();
b.Text = text;
b.AutoSize = true;
b.Location = new Point(0, 0);
//Shift over all other buttons to prevent overlap
//b.Width is incorrect below, because b.AutoSize hasn't taken effect
for (int i = 0; i < Controls.Count; i++)
if (Controls[i] is Button)
Controls[i].Location = new Point(Controls[i].Location.X + b.Width + buffer, Controls[i].Location.Y);
Controls.add(b);
}
Attempt 2
Searched Google and StackOverflow for the following:
c# autosize immediately
c# autosize fast
c# autosize not working
Attempt 3
Asking here.
Last Resort
If nothing else works, a timer could be set to reposition Buttons on each tick. However this is very sloppy design, and doesn't aid in learning the intricacies of AutoSize. I'd like to avoid this workaround if possible.

The AutoSize and AutoSizeMode mode are applied only when the control is parented to the another control or form.
So invoke first
Controls.Add(b);
Now the b.Size will the adjusted accordingly and can be used in the calculations.
Alternatively, instead of Size property you can use the GetPreferredSize method to get the correct size without actually applying AutoSize and use it inside the calculations:
var bSize = b.GetPreferredSize(Size.Empty);
//Shift over all other buttons to prevent overlap
//b.Width is incorrect below, because b.AutoSize hasn't taken effect
for (int i = 0; i < Controls.Count; i++)
if (Controls[i] is Button)
Controls[i].Location = new Point(Controls[i].Location.X + bSize.Width + buffer, Controls[i].Location.Y);

The FlowLayoutPanel control does this work for you.
Place one on your form and try adding buttons in the following manner:
Button b = new Button();
b.AutoSize = true;
b.Text = text;
flowLayoutPanel1.SuspendLayout();
flowLayoutPanel1.Controls.Add(b);
flowLayoutPanel1.Controls.SetChildIndex(b, 0);
flowLayoutPanel1.ResumeLayout();

You can subscribe to the Resize event of the last button added. This will allow you to accurately change the locations of all of the buttons because now all of the buttons have been AutoSized.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
var button1 = NewButton(0);
button1.Location = new Point(10, 10);
var button2 = NewButton(1);
button2.Location = new Point(button1.Right, 10);
var button3 = NewButton(2);
button3.Location = new Point(button2.Right, 10);
button3.Resize += (s, e) =>
{
button2.Location = new Point(button1.Right, 10);
button3.Location = new Point(button2.Right, 10);
};
Controls.Add(button1);
Controls.Add(button2);
Controls.Add(button3);
}
private Button NewButton(int index)
{
return new Button()
{
Text = "ButtonButtonButton" + index.ToString(),
AutoSize = true
};
}
}

Why does my Panel cut the text strangely off?

I have the problem that the text inside my panel gets cut of strangely. The panel is located inside a textbox. But even if I replace the textbox by a flowlayoutpanel, I have the same issue.
Code:
List<string> list = datenbank.FerienAuswahl(monat, jahr);
int i = 0;
//Create Panel
try
{
//Fill Panel
do
{
Label panel = new Label();
panel.Name = "panel" + i;
panel.Height = 30;
panel.Width = 400;
panel.AutoSize = false;
panel.TextAlign = ContentAlignment.MiddleCenter;
panel.ForeColor = Color.Black;
panel.Text = list[i];
Label ferien = new Label();
panel.Controls.Add(ferien);
tbFerien.Controls.Add(panel);
i++;
} while (i < list.Count);
}
catch { }
Result:
I have already tried to change the width of the panel. But as result I only get a messed up alignment of the text.
The only settings of the textbox I have changed are these:
Multiline: True
TextAlign: Center
Size: 359; 125
Does Someone know what else I could try ?

These lines worry me:
Label panel = new Label();
Label ferien = new Label();
panel.Controls.Add(ferien);
tbFerien.Controls.Add(panel);
It seems to me you are adding one label to another. That's not good. Use a Panel or TableLayoutPanel instead of the actual panel and make sure you have your positioning good.

Strange empty spaces in FlowLayoutPanel

I have lots of buttons on flowlayoutpanel, and then there's text labels to break the flow. Last button before label and label itself has SetFlowBreak. All works kind of fine, but what I don't understand, is why there is so much space under the text label? If form is resized so narrow that there's only one column of buttons, then the unwanted space disappears. Can someone explain how that space can be removed?
Code:
public Form1()
{
InitializeComponent();
for (int i = 1; i <= 100; i++)
{
Button button = new Button();
button.Text = i.ToString();
button.Width = 150;
button.Height = 50;
button.Margin = new Padding(5);
flowLayoutPanel1.Controls.Add(button);
if (i % 10 == 0)
{
flowLayoutPanel1.SetFlowBreak(button, true);
Label label = new Label();
label.Text = "Some random text";
label.AutoSize = true;
label.Margin = new Padding(5, 5, 0, 0);
label.BackColor = ColorTranslator.FromHtml("#ccc");
flowLayoutPanel1.Controls.Add(label);
flowLayoutPanel1.SetFlowBreak(label, true);
}
}
}
And couple of images to show what I mean:
Image1: Strange space under the Label
Image2: No space under the Label when the form is resized (this is how I'd like this to work)

Thank you Hans! I thinks this is a real answer, as it solved my problem: (quote from comments)
It is a bug, same one as this one. The extra space is the height of the next label. The workaround is exactly the same, just add a dummy control with a Width of 0 after the label. – Hans Passant
So first I removed flowbreak after the real label:
flowLayoutPanel1.SetFlowBreak(label, true);
And then replaced it with the following code, and the mysterious space disappeared!
Label dummyLabel = new Label();
dummyLabel.Width = 0;
dummyLabel.Height = 0;
dummyLabel.Margin = new Padding(0, 0, 0, 0);
flowLayoutPanel1.Controls.Add(dummyLabel);
flowLayoutPanel1.SetFlowBreak(dummyLabel, true);