I have a Multiline richtextbox control into which i want to integrate the feature of adding a line number. i have considered many approaches
- Add a label and updating the line numbers as the line count changes
- Add a picturebox along with to draw string on it.
- Add another textbox along with and show line numbers on it
- Add listbox along and display line numbers in it.
I got two doubts.
- The richtextbox which i'm using is a custom made control and derieves from RichTextBox class. How can i add multiple controls to it.
- What is the best approach to show line numbers for the multiline text in c#
My own example. All is fine, but wordwrap must be disabled :(
int maxLC = 1; //maxLineCount - should be public
private void rTB_KeyUp(object sender, KeyEventArgs e)
{
int linecount = rTB.GetLineFromCharIndex( rTB.TextLength ) + 1;
if (linecount != maxLC)
{
tB_line.Clear();
for (int i = 1; i < linecount+1; i++)
{
tB_line.AppendText(Convert.ToString(i) + "\n");
}
maxLC = linecount;
}
}
where rTB is my richtextbox and tB is textBox next to rTB
J.T. jr
this code helped me thank you, needed to convert visual basic but could:
Private Sub TextBox1_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles TextBox1.KeyUp
Dim maxlc As Integer = 1
Dim linecount As Integer = TextBox1.GetLineFromCharIndex(TextBox1.Height) + 1
If linecount <> maxlc Then
TextBox2.Clear()
For i = 0 To linecount - 1 Step 1
TextBox2.AppendText(Convert.ToString(i) + vbNewLine)
Next i
maxlc = linecount
End If
End Sub
WORKS 100%!!! But you need to add richTextBox2 for line numbers, if you want change it to other form like listbox, anyway it served me well.
private void richTextBox1_keyDown(object sender, KeyEventArgs e)
{
for (int i = 0; i <= richTextBox1.Lines.Count(); i++)
{
if (!(e.KeyCode == Keys.Back))
{
if (!richTextBox2.Text.Contains(i.ToString()))
{
richTextBox2.Text += i.ToString() + "\n";
}
}
else
{
richTextBox2.Clear();
}
}
}
public int getWidth()
{
int w = 25;
// get total lines of richTextBox1
int line = richTextBox1.Lines.Length;
if (line <= 99)
{
w = 20 + (int)richTextBox1.Font.Size;
}
else if (line <= 999)
{
w = 30 + (int)richTextBox1.Font.Size;
}
else
{
w = 50 + (int)richTextBox1.Font.Size;
}
return w;
}
public void AddLineNumbers()
{
// create & set Point pt to (0,0)
Point pt = new Point(0, 0);
// get First Index & First Line from richTextBox1
int First_Index = richTextBox1.GetCharIndexFromPosition(pt);
int First_Line = richTextBox1.GetLineFromCharIndex(First_Index);
// set X & Y coordinates of Point pt to ClientRectangle Width & Height respectively
pt.X = ClientRectangle.Width;
pt.Y = ClientRectangle.Height;
// get Last Index & Last Line from richTextBox1
int Last_Index = richTextBox1.GetCharIndexFromPosition(pt);
int Last_Line = richTextBox1.GetLineFromCharIndex(Last_Index);
// set Center alignment to LineNumberTextBox
LineNumberTextBox.SelectionAlignment = HorizontalAlignment.Center;
// set LineNumberTextBox text to null & width to getWidth() function value
LineNumberTextBox.Text = "";
LineNumberTextBox.Width = getWidth();
// now add each line number to LineNumberTextBox upto last line
for (int i = First_Line; i <= Last_Line + 2; i++)
{
LineNumberTextBox.Text += i + 1 + "\n";
}
}
private void Form1_Load(object sender, EventArgs e)
{
LineNumberTextBox.Font = richTextBox1.Font;
richTextBox1.Select();
AddLineNumbers();
}
private void richTextBox1_SelectionChanged(object sender, EventArgs e)
{
Point pt = richTextBox1.GetPositionFromCharIndex(richTextBox1.SelectionStart);
if (pt.X == 1)
{
AddLineNumbers();
}
}
private void richTextBox1_VScroll(object sender, EventArgs e)
{
LineNumberTextBox.Text = "";
AddLineNumbers();
LineNumberTextBox.Invalidate();
}
private void richTextBox1_TextChanged(object sender, EventArgs e)
{
if (richTextBox1.Text == "")
{
AddLineNumbers();
}
}
private void richTextBox1_FontChanged(object sender, EventArgs e)
{
LineNumberTextBox.Font = richTextBox1.Font;
richTextBox1.Select();
AddLineNumbers();
}
private void LineNumberTextBox_MouseDown(object sender, MouseEventArgs e)
{
richTextBox1.Select();
LineNumberTextBox.DeselectAll();
}
private void Form1_Resize(object sender, EventArgs e)
{
AddLineNumbers();
}
来源:https://stackoverflow.com/questions/657635/displaying-line-number-in-rich-text-box-c-sharp