C# listBox undo button

David

14y5.3kC#

ok, I have a listBox where I can type something in a textBox and add it to the listBox.
But when I have added it, how do I make a undo button?
And one more question. if i type something new, it starts on a new line. is it possible to avoid that in any way?

3 Replies

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Vulpes14y ago
Accepted answer
To remove the last element added, whether selected or not:

private void btnundo_Click(object sender, EventArgs e)
{
if (listBox1.Items.Count > 0)
{
listBox1.Items.RemoveAt(listBox1.Items.Count - 1);
}
}
David14y ago
ok, thanks it worked, but everytime I use the undo button, I have to select the sentence. is it any way to remove the last thing added?
Satyapriya Nayak14y ago
Hi David,

Try this...

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnadd_Click(object sender, EventArgs e)
        {

            listBox1.SelectedIndex = listBox1.Items.Add(textBox1.Text);
            textBox1.Clear();



        }

        private void btnundo_Click(object sender, EventArgs e)
        {

            if (listBox1.SelectedIndices.Count > 0)
            {
                for (int i = listBox1.SelectedIndices.Count - 1; i >= 0; i--)
                {
                    listBox1.Items.RemoveAt(listBox1.SelectedIndices[i]);
                }
            }

        }
    }
}

Thanks
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