How to add a line to a multiline TextBox?
I would go with the System.Environment.NewLine
or a StringBuilder
Then you could add lines with a string builder like this:
StringBuilder sb = new StringBuilder();
sb.AppendLine("brown");
sb.AppendLine("brwn");
textbox1.Text += sb.ToString();
or NewLine like this:
textbox1.Text += System.Environment.NewLine + "brown";
Better:
StringBuilder sb = new StringBuilder(textbox1.Text);
sb.AppendLine("brown");
sb.AppendLine("brwn");
textbox1.Text = sb.ToString();
@Casperah pointed out that i'm thinking about it wrong:
- A
TextBox
doesn't have lines - it has text
- that text can be split on the CRLF into lines, if requested
- but there is no notion of lines
The question then is how to accomplish what i want, rather than what WinForms lets me.
There are subtle bugs in the other given variants:
textBox1.AppendText("Hello" + Environment.NewLine);
textBox1.AppendText("Hello" + "\r\n");
textBox1.Text += "Hello\r\n"
textbox1.Text += System.Environment.NewLine + "brown";
They either append or prepend a newline when one (might) not be required.
So, extension helper:
public static class WinFormsExtensions
{
public static void AppendLine(this TextBox source, string value)
{
if (source.Text.Length==0)
source.Text = value;
else
source.AppendText("\r\n"+value);
}
}
So now:
textBox1.Clear();
textBox1.AppendLine("red");
textBox1.AppendLine("green");
textBox1.AppendLine("blue");
and
textBox1.AppendLine(String.Format("Processing file {0}", filename));
Note: Any code is released into the public domain. No attribution required.