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How to connect .DrawEllipse with .DrawString

I'm trying to write text inside circle (not centered by rectangle) alignment must be from line to line inside circle.
I have successfully drawn the circle and text. I did research on Stack Overflow and Google without success about putting text inside this circle.
private void Button1_Click(object sender, EventArgs e)
{
System.Drawing.Graphics graphicsObj;
graphicsObj = this.CreateGraphics();
// Create font and brush.
Font drawFont = new Font("Arial", 5);
SolidBrush drawBrush = new SolidBrush(Color.Black);
// Create point for upper-left corner of drawing.
float x = 150.0F;
float y = 50.0F;
// Set format of string.
StringFormat drawFormat = new StringFormat();
drawFormat.FormatFlags = StringFormatFlags.FitBlackBox;
graphicsObj.DrawEllipse(Pens.Red, 20, 20, 350, 350);
graphicsObj.DrawString(richTextBox1.Text.ToString(), drawFont, drawBrush, x, y, drawFormat);
}
Looking for advise, not for exact code..
-> How to establish connection for text alignment based on rectangle.
Expected output like in this image : https://imge.to/i/miFif
exactly same but I need in C# Win.Form -> Wrap text inside a circular div

DrawString has an overload with format options:
...
DrawString(e.Cache, text, rect,
new StringFormat() {
LineAlignment = StringAlignment.Center,
Alignment = StringAlignment.Center
});

Finding the bounding rectangle of text with alignment

I'm trying to draw a box around a label which has been aligned using StringAlignment.Far for example. I can find the Size of text using g.MeasureString but I can't find a method to translate the origin point such that I can find a Rectangle which bounds the text.
Say I have a Point origin at which to draw from, and a StringFormat format with what alignment I wish my string to have. I can find the Size of the string using g.MeasureString(text, font). How do I translate this Point/Size pair into a rectangle which overlaps the g.DrawString(text, font, brush, origin, format) call.

It's difficult to convert c to managed code. You should use .Net code directly if it's available.
For MeasureString, see link Graphics.MeasureString Method
Example:
using System.Diagnostics;
...
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Graphics g = e.Graphics;
Font font = new Font("Arial", 16);
SizeF sz = g.MeasureString("Text...", font);
Rectangle rc = new Rectangle(0,0, (int)sz.Width, (int)sz.Height);
Debug.WriteLine(rc.Width.ToString());
Debug.WriteLine(rc.Height.ToString());
//change top/left origin of rectangle
rc.X = 10;
rc.Y = 20;
}
You just need the width and height of text. You can change left/top corner of rectangle.
By the way, the C method gives a rectangle with top/left coordinates at zero, so it's the same information as Size
Edit
This will fit text with word-break flag in to a rectangle whose width is 100. The height of the rectangle is not known. TextRenderer.MeasureText will tell us the height of the rectangle. Top/left corner can be changed, alignment can be changed.
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Font font = new Font("Arial", 10);
string text = "I'm trying to draw a box around a label which has been aligned.";
Size layout = new Size(100, 0);
Size sz = TextRenderer.MeasureText(e.Graphics, text, font, layout,
TextFormatFlags.WordBreak);
Rectangle rc = new Rectangle(new Point(0,0), sz);
e.Graphics.DrawRectangle(Pens.Black, rc);
TextRenderer.DrawText(e.Graphics, text, font, rc,
SystemColors.ControlText, SystemColors.Control, TextFormatFlags.WordBreak);
}

My way is use SetMeasurableCharacterRanges to obtain the region of the whole text.
Consider into OnPaint:
protected override void OnPaint(PaintEventArgs e)
{
Graphics g = e.Graphics;
Font font = new Font("Arial", 16);
string text = "Border of this text";
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
RectangleF area = new RectangleF(0, 0, 246, 84);
sf.SetMeasurableCharacterRanges(new CharacterRange[] { new CharacterRange(0, text.Length) });
Region[] r = g.MeasureCharacterRanges(text, font, area, sf);
Rectangle rf = new Rectangle((int)r[0].GetBounds(g).X, (int)r[0].GetBounds(g).Y, (int)r[0].GetBounds(g).Width, (int)r[0].GetBounds(g).Height);
g.DrawString(text, font, Brushes.Black, area, sf);
g.DrawRectangle(new Pen(Color.Red, 1), rf);
}

Dynamically resizing font to fit space while using Graphics.DrawString

Does anyone have a tip whereas you could dynamically resize a font to fit a specific area? For example, I have an 800x110 rectangle and I want to fill it with the max size font that would support the entire string I'm trying to display.
Bitmap bitmap = new Bitmap(800, 110);
using (Graphics graphics = Graphics.FromImage(bitmap))
using (Font font1 = new Font("Arial", 120, FontStyle.Regular, GraphicsUnit.Pixel))
{
Rectangle rect1 = new Rectangle(0, 0, 800, 110);
StringFormat stringFormat = new StringFormat();
stringFormat.Alignment = StringAlignment.Center;
stringFormat.LineAlignment = StringAlignment.Center;
graphics.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;
graphics.DrawString("Billy Reallylonglastnameinstein", font1, Brushes.Red, rect1, stringFormat);
}
bitmap.Save(Server.MapPath("~/Fonts/" + System.Guid.NewGuid() + ".png"));
Obviously that whole name won't render in the space provided at the large font size. There has to be a simple way to do this?

You should do a scale transform on Font.Size the following function is an example of doing that but you can improve it to apply better results.
Here is FindFont function which get a room and a text with prefered size and gives you a font in which you can set that whole text fits the room!
// This function checks the room size and your text and appropriate font
// for your text to fit in room
// PreferedFont is the Font that you wish to apply
// Room is your space in which your text should be in.
// LongString is the string which it's bounds is more than room bounds.
private Font FindFont(
System.Drawing.Graphics g,
string longString,
Size Room,
Font PreferedFont
) {
// you should perform some scale functions!!!
SizeF RealSize = g.MeasureString(longString, PreferedFont);
float HeightScaleRatio = Room.Height / RealSize.Height;
float WidthScaleRatio = Room.Width / RealSize.Width;
float ScaleRatio = (HeightScaleRatio < WidthScaleRatio)
? ScaleRatio = HeightScaleRatio
: ScaleRatio = WidthScaleRatio;
float ScaleFontSize = PreferedFont.Size * ScaleRatio;
return new Font(PreferedFont.FontFamily, ScaleFontSize);
}
For your question you can call it like the following code:
Bitmap bitmap = new Bitmap(800, 110);
using (System.Drawing.Graphics graphics = System.Drawing.Graphics.FromImage(bitmap))
using (Font font1 = new Font("Arial", 120, FontStyle.Regular, GraphicsUnit.Pixel))
{
Rectangle rect1 = new Rectangle(0, 0, 800, 110);
StringFormat stringFormat = new StringFormat();
stringFormat.Alignment = StringAlignment.Center;
stringFormat.LineAlignment = StringAlignment.Center;
graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
Font goodFont = FindFont(graphics, "Billy Reallylonglastnameinstein", rect1.Size, font1);
graphics.DrawString(
"Billy Reallylonglastnameinstein",
goodFont,
Brushes.Red,
rect1,
stringFormat
);
}

I've adapted Saeed's great function to more suit my requirements. Comments explain all:
// You hand this the text that you need to fit inside some
// available room, and the font you'd like to use.
// If the text fits nothing changes
// If the text does not fit then it is reduced in size to
// make it fit.
// PreferedFont is the Font that you wish to apply
// FontUnit is there because the default font unit is not
// always the one you use, and it is info required in the
// constructor for the new Font.
public static void FindGoodFont(Graphics Graf, string sStringToFit,
Size TextRoomAvail,
ref Font FontToUse,
GraphicsUnit FontUnit)
{
// Find out what the current size of the string in this font is
SizeF RealSize = Graf.MeasureString(sStringToFit, FontToUse);
Debug.WriteLine("big string is {0}, orig size = {1},{2}",
sStringToFit, RealSize.Width, RealSize.Height);
if ((RealSize.Width <= TextRoomAvail.Width) && (RealSize.Height <= TextRoomAvail.Height))
{
Debug.WriteLine("The space is big enough already");
// The current font is fine...
return;
}
// Either width or height is too big...
// Usually either the height ratio or the width ratio
// will be less than 1. Work them out...
float HeightScaleRatio = TextRoomAvail.Height / RealSize.Height;
float WidthScaleRatio = TextRoomAvail.Width / RealSize.Width;
// We'll scale the font by the one which is furthest out of range...
float ScaleRatio = (HeightScaleRatio < WidthScaleRatio) ? ScaleRatio = HeightScaleRatio : ScaleRatio = WidthScaleRatio;
float ScaleFontSize = FontToUse.Size * ScaleRatio;
Debug.WriteLine("Resizing with scales {0},{1} chose {2}",
HeightScaleRatio, WidthScaleRatio, ScaleRatio);
Debug.WriteLine("Old font size was {0}, new={1} ",FontToUse.Size,ScaleFontSize);
// Retain whatever the style was in the old font...
FontStyle OldFontStyle = FontToUse.Style;
// Get rid of the old non working font...
FontToUse.Dispose();
// Tell the caller to use this newer smaller font.
FontToUse = new Font(FontToUse.FontFamily,
ScaleFontSize,
OldFontStyle,
FontUnit);
}

This is just an update for #Saeed's FindFont function.
GraphicsUnit.Pixel needs to be added to FindFont function return line. Without GraphicsUnit.Pixel, system dpi will effect the drawn string. Problem will arise when the dpi of system and bitmap mismatches. You can see more detail in this Windows DPI setting affects Graphics.DrawString. Since GraphicsUnit of PreferedFont is already set to GraphicsUnit.Pixel and return font is not set with GraphicsUnit.Pixel. In this case text will go out of the Room dimension, if bitmap dpi is larger than system dpi and font size will go smaller than the expected size if bitmap dpi is smaller than system dpi. Here is the updated function.
private Font FindFont( System.Drawing.Graphics g , string longString , Size Room , Font PreferedFont)
{
SizeF RealSize = g.MeasureString(longString, PreferedFont);
float HeightScaleRatio = Room.Height / RealSize.Height;
float WidthScaleRatio = Room.Width / RealSize.Width;
float ScaleRatio = (HeightScaleRatio < WidthScaleRatio) ? ScaleRatio = HeightScaleRatio : ScaleRatio = WidthScaleRatio;
float ScaleFontSize = PreferedFont.Size * ScaleRatio;
return new Font(PreferedFont.FontFamily, ScaleFontSize,PreferedFont.Style,GraphicsUnit.Pixel);
}

I don't want to bash against saaeds solution which is probably pretty awesome, too. But I found another one on msdn: Dynamic Graphic Text Resizing which worked for me.
public Font GetAdjustedFont(Graphics GraphicRef, string GraphicString, Font OriginalFont, int ContainerWidth, int MaxFontSize, int MinFontSize, bool SmallestOnFail)
{
// We utilize MeasureString which we get via a control instance
for (int AdjustedSize = MaxFontSize; AdjustedSize >= MinFontSize; AdjustedSize--)
{
Font TestFont = new Font(OriginalFont.Name, AdjustedSize, OriginalFont.Style);
// Test the string with the new size
SizeF AdjustedSizeNew = GraphicRef.MeasureString(GraphicString, TestFont);
if (ContainerWidth > Convert.ToInt32(AdjustedSizeNew.Width))
{
// Good font, return it
return TestFont;
}
}
// If you get here there was no fontsize that worked
// return MinimumSize or Original?
if (SmallestOnFail)
{
return new Font(OriginalFont.Name,MinFontSize,OriginalFont.Style);
}
else
{
return OriginalFont;
}
}

Here is my solution that support wrapping.
public static Font GetAdjustedFont(Graphics graphic, string str, Font originalFont, Size containerSize)
{
// We utilize MeasureString which we get via a control instance
for (int adjustedSize = (int)originalFont.Size; adjustedSize >= 1; adjustedSize--)
{
var testFont = new Font(originalFont.Name, adjustedSize, originalFont.Style, GraphicsUnit.Pixel);
// Test the string with the new size
var adjustedSizeNew = graphic.MeasureString(str, testFont, containerSize.Width);
if (containerSize.Height > Convert.ToInt32(adjustedSizeNew.Height))
{
// Good font, return it
return testFont;
}
}
return new Font(originalFont.Name, 1, originalFont.Style, GraphicsUnit.Pixel);
}
How to use:
var font = GetAdjustedFont(drawing, text, originalfont, wrapSize);
drawing.DrawString(text, font, textBrush, new Rectangle(0, 0, wrapSize.Width, wrapSize.Height));

Calculating the minimum width needed to show text in X lines, in .Net?

How could you calculate the minimum width needed to display a string in X lines, given that text should break on whitespace?

Possible Hint: Perhaps some sort of binary search using Graphics.MeasureString()?

Edit: Didn't realize you wanted to try and fit the text to a fixed number of lines. This was a tough one to try and solve. This is the best I could come up with and may not be the most elegant, but it seems to work:
public SizeF CalculateWidth(Font font, Graphics graphics, int numOfLines,
string text)
{
SizeF sizeFull = graphics.MeasureString(text, font,
new SizeF(
float.PositiveInfinity,
float.PositiveInfinity),
StringFormat.
GenericTypographic);
float width = sizeFull.Width/numOfLines;
float averageWidth = sizeFull.Width/text.Length;
int charsFitted;
int linesFilled;
SizeF needed = graphics.MeasureString(text, font,
new SizeF(width,
float.
PositiveInfinity),
StringFormat.
GenericTypographic,
out charsFitted,
out linesFilled);
while (linesFilled > numOfLines)
{
width += averageWidth;
needed = graphics.MeasureString(text, font,
new SizeF(width,
float.PositiveInfinity),
StringFormat.GenericTypographic,
out charsFitted, out linesFilled);
}
return needed;
}
Example usage:
Font font = new Font("Arial", 12, FontStyle.Regular,
GraphicsUnit.Pixel);
Graphics g = Graphics.FromImage(new Bitmap(1, 1));
string text = "Some random text with words in it.";
SizeF size = CalculateWidth(font, g, 3, text);

Center text output from Graphics.DrawString()

I'm using the .NETCF (Windows Mobile) Graphics class and the DrawString() method to render a single character to the screen.
The problem is that I can't seem to get it centred properly. No matter what I set for the Y coordinate of the location of the string render, it always comes out lower than that and the larger the text size the greater the Y offset.
For example, at text size 12, the offset is about 4, but at 32 the offset is about 10.
I want the character to vertically take up most of the rectangle it's being drawn in and be centred horizontally. Here's my basic code. this is referencing the user control it's being drawn in.
Graphics g = this.CreateGraphics();
float padx = ((float)this.Size.Width) * (0.05F);
float pady = ((float)this.Size.Height) * (0.05F);
float width = ((float)this.Size.Width) - 2 * padx;
float height = ((float)this.Size.Height) - 2 * pady;
float emSize = height;
g.DrawString(letter, new Font(FontFamily.GenericSansSerif, emSize, FontStyle.Regular),
new SolidBrush(Color.Black), padx, pady);
Yes, I know there is the label control that I could use instead and set the centring with that, but I actually do need to do this manually with the Graphics class.

I'd like to add another vote for the StringFormat object.
You can use this simply to specify "center, center" and the text will be drawn centrally in the rectangle or points provided:
StringFormat format = new StringFormat();
format.LineAlignment = StringAlignment.Center;
format.Alignment = StringAlignment.Center;
However there is one issue with this in CF. If you use Center for both values then it turns TextWrapping off. No idea why this happens, it appears to be a bug with the CF.

To align a text use the following:
StringFormat sf = new StringFormat();
sf.LineAlignment = StringAlignment.Center;
sf.Alignment = StringAlignment.Center;
e.Graphics.DrawString("My String", this.Font, Brushes.Black, ClientRectangle, sf);
Please note that the text here is aligned in the given bounds. In this sample this is the ClientRectangle.

Through a combination of the suggestions I got, I came up with this:
private void DrawLetter()
{
Graphics g = this.CreateGraphics();
float width = ((float)this.ClientRectangle.Width);
float height = ((float)this.ClientRectangle.Width);
float emSize = height;
Font font = new Font(FontFamily.GenericSansSerif, emSize, FontStyle.Regular);
font = FindBestFitFont(g, letter.ToString(), font, this.ClientRectangle.Size);
SizeF size = g.MeasureString(letter.ToString(), font);
g.DrawString(letter, font, new SolidBrush(Color.Black), (width-size.Width)/2, 0);
}
private Font FindBestFitFont(Graphics g, String text, Font font, Size proposedSize)
{
// Compute actual size, shrink if needed
while (true)
{
SizeF size = g.MeasureString(text, font);
// It fits, back out
if (size.Height <= proposedSize.Height &&
size.Width <= proposedSize.Width) { return font; }
// Try a smaller font (90% of old size)
Font oldFont = font;
font = new Font(font.Name, (float)(font.Size * .9), font.Style);
oldFont.Dispose();
}
}
So far, this works flawlessly.
The only thing I would change is to move the FindBestFitFont() call to the OnResize() event so that I'm not calling it every time I draw a letter. It only needs to be called when the control size changes. I just included it in the function for completeness.

To draw a centered text:
TextRenderer.DrawText(g, "my text", Font, Bounds, ForeColor, BackColor,
TextFormatFlags.HorizontalCenter |
TextFormatFlags.VerticalCenter |
TextFormatFlags.GlyphOverhangPadding);
Determining optimal font size to fill an area is a bit more difficult. One working soultion I found is trial-and-error: start with a big font, then repeatedly measure the string and shrink the font until it fits.
Font FindBestFitFont(Graphics g, String text, Font font,
Size proposedSize, TextFormatFlags flags)
{
// Compute actual size, shrink if needed
while (true)
{
Size size = TextRenderer.MeasureText(g, text, font, proposedSize, flags);
// It fits, back out
if ( size.Height <= proposedSize.Height &&
size.Width <= proposedSize.Width) { return font; }
// Try a smaller font (90% of old size)
Font oldFont = font;
font = new Font(font.FontFamily, (float)(font.Size * .9));
oldFont.Dispose();
}
}
You'd use this as:
Font bestFitFont = FindBestFitFont(g, text, someBigFont, sizeToFitIn, flags);
// Then do your drawing using the bestFitFont
// Don't forget to dispose the font (if/when needed)

Here's some code. This assumes you are doing this on a form, or a UserControl.
Graphics g = this.CreateGraphics();
SizeF size = g.MeasureString("string to measure");
int nLeft = Convert.ToInt32((this.ClientRectangle.Width / 2) - (size.Width / 2));
int nTop = Convert.ToInt32((this.ClientRectangle.Height / 2) - (size.Height / 2));
From your post, it sounds like the ClientRectangle part (as in, you're not using it) is what's giving you difficulty.

You can use an instance of the StringFormat object passed into the DrawString method to center the text.
See Graphics.DrawString Method and StringFormat Class.