Display Tooltips for MouseHover Text

Question

In this regard, q: Displays a hint when you hover over text

How can I do the same for a keyword in a RichTextBox, but not for a link.

Example:

in a RichTextBox, I type:

Hello world, how are you?

I set Hovering to the word “World” for a tooltip, and when it pops up, ToolTip will appear saying “this is the world”!

but if it is above the RichTextBox or in the word "World" itself, a tooltip will be displayed.

I hope you can help me. More energy and godless!

Answer 1

It is a little simple. You must use the GetCharIndexFromPosition method of your RichTextBox to get the Char index under the Mouse Pointer , do a few simple loops to find the whole word, and then show it in Tooltip popup in normal mode. Here is the code:

  string punctuations = " ,.;!?'\")]}\n"; //This saves your words with their corresponding definitions/details Dictionary<string, string> dict = new Dictionary<string, string>(StringComparer.CurrentCultureIgnoreCase); ToolTip tt = new ToolTip(); int k; int lineBreakIndex = 60; int textHeight; //MouseMove event handler for your richTextBox1 private void richTextBox1_MouseMove(object sender, MouseEventArgs e){ if (richTextBox1.TextLength == 0) return; Point lastCharPoint = richTextBox1.GetPositionFromCharIndex(richTextBox1.TextLength - 1); if (eY > textHeight || (eY >= lastCharPoint.Y && eX > lastCharPoint.X + textHeight - lastCharPoint.Y)) { tt.Hide(richTextBox1); k = -1; return; } int i = richTextBox1.GetCharIndexFromPosition(e.Location); int m = i, n = i; while (m>-1&&!punctuations.Contains(richTextBox1.Text[m])) m--; m++; while (n<richTextBox1.TextLength&&!punctuations.Contains(richTextBox1.Text[n])) n++; if (n > m){ string word = richTextBox1.Text.Substring(m, n - m); if (dict.ContainsKey(word)){ if (k != m){ tt.ToolTipTitle = word; tt.Show(dict[word], richTextBox1, eX, eY + 10); k = m; } } else{ tt.Hide(richTextBox1); k = -1; } } } //This will get the entry text with lines broken. private string GetEntryText(string key){ string s = dict[key]; int lastLineEnd = lineBreakIndex; for (int i = lastLineEnd; i < s.Length; i += lineBreakIndex) { while (s[i] != ' '){ if (--i < 0) break; } i++; s = s.Insert(i, "\n"); lastLineEnd = i+1; } return s; } //MouseLeave event handler for your richTextBox1 private void richTextBox1_MouseLeave(object sender, EventArgs e){ tt.Hide(richTextBox1); k = -1; } //ContentsResized event handler for your richTextBox1 private void richTextBox1_ContentsResized(object sender, ContentsResizedEventArgs e) { textHeight = e.NewRectangle.Height; } //Here are some sample words with definitions: dict.Add("world", "- World is a common name for the whole of human civilization, specifically human experience, history, or the human condition in general, worldwide, ie anywhere on Earth."); dict.Add("geek", "- A person who is single-minded or accomplished in scientific or technical pursuits but is felt to be socially inept");