Adding new line of data to TextBox

Brandon Ling picture Brandon Ling · Nov 10, 2012 · Viewed 192.1k times · Source

I'm doing a chat client, and currently I have a button that will display data to a multi-line textbox when clicked. Is this the only way to add data to the multi-line textbox? I feel this is extremely inefficient, because if the conversation gets really long the string will get really long as well.

private void button1_Click(object sender, EventArgs e)
        {
            string sent = chatBox.Text;
            displayBox.Text += sent + "\r\n";

        }

Answer

user1693593 picture user1693593 · Nov 10, 2012

If you use WinForms:

Use the AppendText(myTxt) method on the TextBox instead (.net 3.5+):

    private void button1_Click(object sender, EventArgs e)
    {
        string sent = chatBox.Text;

        displayBox.AppendText(sent);
        displayBox.AppendText(Environment.NewLine);

    }

Text in itself has typically a low memory footprint (you can say a lot within f.ex. 10kb which is "nothing"). The TextBox does not render all text that is in the buffer, only the visible part so you don't need to worry too much about lag. The slower operations are inserting text. Appending text is relatively fast.

If you need a more complex handling of the content you can use StringBuilder combined with the textbox. This will give you a very efficient way of handling text.