Updating a list box

[sbandalli]

Hello All,

I am trying to udapte a listbox as suggested like this,but it gives me error.Please help...

        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
 
            int index = listBox1.SelectedIndex;
            Console.WriteLine("Index is {0}",index );
            listBox1.Items[index] = textBox1.Text; 
        }
 

No matter which item I select in the Listbox,the index ( listBox1.Items[index]) always it takes as -1. Error:::InvalidArgument = Value of '-1' is not a valid index.

but when I print the index value using Console.writeLine it prints the correct slected index. I am not able to figure out the reason.

Thank you all

[falaque]

use if(index>=0) and put your code inside it.