Reputation: 69
I am making a projectile motion simulation program for my A level Computing project and I need to use physics notation with subscripts. I have no idea how to use this in a label or a rich text box. Can anyone please give me help/code to implement this?
Upvotes: 0
Views: 1644
Reputation: 1
SelectioncharOffset is not your best option. Is is better to manipulate the rtf and add the subscript labels.
//This allows you to reselect the text in the rtb after formatting
int SelectionStart = richTextBox1.SelectionStart;
int SelectionLength = richTextBox1.SelectionLength;
string selectedRtf = richTextBox1.SelectedRtf;
int Start;
int End;
string pre;
string Mid;
string post;
//remove superscript from selected text
Start = selectedRtf.IndexOf("\\super");
while (Start != -1)
{
pre = selectedRtf.Substring(0, Start);
post = selectedRtf.Substring(Start + 6, selectedRtf.Length - (Start + 6));
selectedRtf = pre.Trim() + post.Trim();
Start = selectedRtf.IndexOf("\\super");
}
//if selected text does not contain subscript
if (selectedRtf.IndexOf("\\sub") == -1 && selectedRtf.IndexOf("\\nosupersub") == -1)
{
Start = selectedRtf.IndexOf("}}") + 2;
End = selectedRtf.IndexOf("}", Start);
pre = selectedRtf.Substring(0, Start);
Mid = selectedRtf.Substring(Start, End - Start);
post = selectedRtf.Substring(End, selectedRtf.Length - End);
selectedRtf = pre + "\\sub" + Mid + "\\nosupersub" + post;
goto Clean;
}
//if selected text contains subscript
if (selectedRtf.IndexOf("\\sub") > 0)
{
Start = selectedRtf.IndexOf("\\sub");
while (Start != -1)
{
pre = selectedRtf.Substring(0, Start);
post = selectedRtf.Substring(Start + 4, selectedRtf.Length - (Start + 4));
selectedRtf = pre.Trim() + post.Trim();
Start = selectedRtf.IndexOf("\\sub");
}
goto Clean;
}
Clean:
richTextBox1.SelectedRtf = selectedRtf;
richTextBox1.Focus();
richTextBox1.SelectionStart = SelectionStart;
richTextBox1.SelectionLength = SelectionLength;
Upvotes: 0
Reputation: 180868
You need to use the SelectionCharOffset property in a RichTextBox to accomplish this.
For subscript, make the number negative, like this:
richTextBox1.SelectionCharOffset = -10;
Upvotes: 2