I am trying to use FormattedText.BuildGeometry to determine how the characters are laid out, in order to determine the logical position of the mouse. In my context, the FormattedText can be assumed to be a single line - I should get a geometry group with 1 child, which has a child geometry for each character. This is true except that for the characters "f" and "t", repeating the character in the text of the FormattedText will cause the number of geometries on the line to be one less than the number of characters in the text.
Example code:
var tf = new Typeface(new FontFamily("Calibri"), FontStyles.Normal, FontWeights.Normal, FontStretches.Normal);
var ft = new FormattedText("ff", CultureInfo.CurrentCulture, FlowDirection.LeftToRight, tf, 14, Brushes.Black);
var g = ft.BuildGeometry(new Point(0, 0));
var gc = (GeometryGroup)((GeometryGroup)g).Children[0];
Debug.Assert(gc.Children.Count == ft.Text.Length, "Expected length of " + ft.Text.Length + " but found " + gc.Children.Count);
You can just attach this to a button in an empty WPF application.
This fails for anything that contains "ff" or "tt". Changing the font changes the behaviour - some fonts I haven't found characters that cause this.
The short answer is that BuildGeometry thinks in glyphs, not characters. From the documentation (emphasis mine):
Returns a Geometry object that represents the formatted text, including all glyphs and text decorations.
In several fonts, "ff" and "tt" are ligatures, so they are represented by a single glyph.
See this question for an explanation of how to do what you wish. Basically, BuildHighlightGeometry(Point, int, int) can return the bounding box for individual characters. You can iterate over the bounding boxes and perform hit tests until you find the character that matches.
Related
I have a richtextbox named rtbDisclaimer. It's set to limit user input to 500 characters. I have been trying to figure out a way to take whatever the user types into the rtb, and break it into an array of strings with each string element limited to a certain character length, such as 100 for example, however if the 100th character is in the middle of a word I don't want it to include that word, but rather to put it in the next element so that words are not cut in half. Basically, if a user types in 500 characters, the whole thing would be broken into 5 or 6 string array elements with each element limited to 100 characters maximum without cutting any words in half. I've searched around and haven't been able to find anything that would work, and can't quite figure out how to tackle this problem. Also, the user input can be any length up to 500, so this would need to be flexible to allow for a input ranging anywhere from 0 - 500 characters.
Ex:
Not this:
[0]This is the user input typed into the ri
[1]chtextbox as it would appear in the ar
[2]ray elements
~~~~~~~~~~~~~~~~~~~~~~~~
This:
[0]This is the user input typed into the
[1]richtextbox as it would appear in the
[2]array elements
Something like this maybe?
var longText = "this morning, bla blabla";
var words = longText.split(' '); // split on space
var sentences = new List<string>();
var currentSentence = string.Empty();
foreach(var word in words){
if((sentence.Length + word.Length + 1) < 100){
currentSentence += word + " ";
}
else{
sentences.Add(currentSentence);
currentSentence = word;
}
}
I am building a report using StringBuilder and the details of it to be properly intended and aligned
for which i will be using
private static int paperWidth = 55; //it defines the size of paper
private static readonly string singleLine = string.Empty.PadLeft(paperWidth, '-');
StringBuilder reportLayout;
reportLayout.AppendLine("\t" + "Store Name");
I want Store Name in center and many such more feilds by use of \t
Thanks in Advance.
EDIT
I want to print like. Store Name in center
If you're simulating what tabs look like at a terminal you should
stick with 8 spaces per tab. A Tab character shifts over to the next
tab stop. By default, there is one every 8 spaces. But in most shells
you can easily edit it to be whatever number of spaces you want
You can realize this through the following Code:
string tab = "\t";
string space = new string(' ', 8);
StringBuilder str = new StringBuilder();
str.AppendLine(tab + "A");
str.AppendLine(space + "B");
string outPut = str.ToString(); // will give two lines of equal length
int lengthOfOP = outPut.Length; //will give you 15
From the above example we can say that in .Net the length of \t is
calculated as 1
A Tab is a Tab and its meaning is created by the application that renders it.
Think of a word processor where a Tab means:
Go to the next tab stop.
You can define the tab stops!
To center output do not use Tabs, use the correct StringFormat :
StringFormat fmt = new StringFormat()
{ Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center };
This centers the text inside a rectanlge in both directions:
e.Graphics.DrawString(someText, someFont, someBrush, layoutRectangle, fmt);
or something like it..
But it looks as if you want to embed the centering inside a text.
This will only work if you really know everything about the output process, i.e. the device, the Font and Size as well as the margins etc..
So it will probably not be reliable at all, no matter what you do.
The best alternative may be to either give up on plain text or use a fixed number of spaces to 'mean' 'centered' and then watch for this number when you render.
If you don't have control over the rendering, it will not work.
so i have a string of characters that are typically formatted like this:
" text" where the bold character is red.
i want to display these types of strings in a richtextbox with the bold character being red.
i have the text in a string variable and i have the location of the red character (in the string) in an int variable.
my solution is:
get characters before the red character
get red character
get characters after the red character
display characters before the red character
display red character (with foreground = Brushes.Red)
display characters after the red characters
this is what i've got so far:
https://github.com/icebbyice/rapide/blob/master/rapide/SpreadWindow.xaml.cs
find: "//stackoverflow" (also, seperateOutputs is not completed)
i stopped there because i thought there had to be a more efficient way to do it because i will be changing the content of the rich text box often (up to 1000 content changes / 60 seconds).
so, is there a better way to do this?
You could do this:
// getting keywords/functions
string keywords = #"\b(e)\b";
MatchCollection keywordMatches = Regex.Matches(codeRichTextBox.Text, keywords);
// saving the original caret position + forecolor
int originalIndex = codeRichTextBox.SelectionStart;
int originalLength = codeRichTextBox.SelectionLength;
Color originalColor = Color.Black;
// MANDATORY - focuses a label before highlighting (avoids blinking)
menuStrip1.Focus();
// removes any previous highlighting (so modified words won't remain highlighted)
codeRichTextBox.SelectionStart = 0;
codeRichTextBox.SelectionLength = codeRichTextBox.Text.Length;
codeRichTextBox.SelectionColor = originalColor;
// scanning...
foreach (Match m in keywordMatches)
{
codeRichTextBox.SelectionStart = m.Index;
codeRichTextBox.SelectionLength = m.Length;
codeRichTextBox.SelectionFont = new Font(codeRichTextBox.Font, FontStyle.Bold);
}
// restoring the original colors, for further writing
codeRichTextBox.SelectionStart = originalIndex;
codeRichTextBox.SelectionLength = originalLength;
codeRichTextBox.SelectionColor = originalColor;
codeRichTextBox.SelectionFont = new Font(codeRichTextBox.Font, FontStyle.Regular);
// giving back the focus
codeRichTextBox.Focus();
That belongs in the RichTextBox TextChanged Event
If you type e, it will display it Bold. Any other text will be displayed as Font.Regular
If you would like to change the syntax from e, then look at the keywords string
This is all I have for this, I hope it helps you :)
I'm using a RichTextBox for coloured text. Let's assume I want to use different colours for different portions of the text. This is working fine so far.
I'm currently having a problem with the SelectionStart property of the RichTextBox. I've set some text to the Text property of the RichTextBox. If the text contains \r\n\r\n the SelectionStart Position won't match the position of characters with the assigned String.
Small example (WinformsApplication. Form with a RichTextBox):
public Form1()
{
InitializeComponent();
String sentence1 = "This is the first sentence.";
String sentence2 = "This is the second sentence";
String text = sentence1 + "\r\n\r\n" + sentence2;
int start1 = text.IndexOf(sentence1);
int start2 = text.IndexOf(sentence2);
this.richTextBox1.Text = text;
String subString1 = text.Substring(start1, sentence1.Length);
String subString2 = text.Substring(start2, sentence2.Length);
bool match1 = (sentence1 == subString1); // true
bool match2 = (sentence2 == subString2); // true
this.richTextBox1.SelectionStart = start1;
this.richTextBox1.SelectionLength = sentence1.Length;
this.richTextBox1.SelectionColor = Color.Red;
this.richTextBox1.SelectionStart = start2;
this.richTextBox1.SelectionLength = sentence2.Length;
this.richTextBox1.SelectionColor = Color.Blue;
}
The RichTextBox looks like this:
As you can see, the first two characters of the second sentence are not coloured. This is the result of an offset produced by \r\n\r\n.
What is the reason for this? Should I use another control for colouring text?
How do I fix the problem in a reliable way? I've tried replacing the "\r\n\r\n"with a String.Empty, but that produces other offset problem.
Related question:
Inconsistent behaviour between in RichTextBox.Select with SubString method
It seems that the sequence \r\n counts for one character only when doing selections. You can do the measurements in a copy of the string where all \r\n are replaced by \n.
Just for completeness (I'll stick to linepogls answer for now):
I've found another way to get indices for the SelectionStart property. The RichTextBox offers a Find method, that can be used to retrieve index positions based on a specified string.
Be aware of the fact, that the text you want to highlight might not be unique and occur multiple times. You can use an overload to specify a start position for the search.
I'm working on a custom RichTextBox which highlights certain words typed in it.
(more like highlight certain strings, because I intent to highlight strings that are not separated by spaces)
I search for strings by loading the text to memory, and looking for a list of strings one by one, then applying formatting to them.
Issue is that, index I get from the plain text representation, doesn't necessarily point to the same position in the RichTextBox's content, when formatting is applied.
(First formatting is perfect. Any subsequent formatting starts to slip to the left. I assume this is because formatting adds certain elements to the documents which makes my indexes incorrect.)
Sample pseudo code for this is as follows.
// get the current text
var text = new TextRange(Document.ContentStart, Document.ContentEnd).Text;
// loop through and highlight
foreach (string entry in WhatToHighlightCollection)
{
var currentText = text;
var nextOccurance = currentText.IndexOf(suggestion); //This index is Unreliable !!!
while (nextOccurance != -1)
{
// Get the offset from start. (There appears to be 2 characters in the
// beginning. I assume this is document and paragraph start tags ??
// So add 2 to it.)
int offsetFromStart = (text.Length) - (currentText.Length) + 2;
var startPointer = Document.ContentStart.
GetPositionAtOffset(offsetFromStart + nextOccurance, LogicalDirection.Forward);
var endPointer = startPointer.GetPositionAtOffset(suggestion.Length, LogicalDirection.Forward);
var textRange = new TextRange(startPointer, endPointer);
textRange.ApplyPropertyValue(TextElement.BackgroundProperty, new SolidColorBrush(Colors.Yellow));
textRange.ApplyPropertyValue(TextElement.FontWeightProperty, FontWeights.Bold);
textRange.ApplyPropertyValue(TextElement.FontFamilyProperty, new FontFamily("Segoe UI"));
// Go to the next occurance.
currentText = currentText.Substring(nextOccurance + suggestion.Length);
nextOccurance = currentText.IndexOf(suggestion);
}
}
How do I map string indexes to rich text box content ?
NOTE: I'm not worried about the performance of this at the moment, although any suggestions are always welcome, as currently I run this on every TextChanged event to highlight 'as the user type' and it's getting a bit sluggish.