How can I find listbox item index with item value?

Question

my

MessageBox.Show(listbox.Items[0].ToString());

is

"abber"

how can I find listbox item index 0 with "abber"?

Answer 1

 int index = listBox1.Items.IndexOf("Specify string here");

Answer 2

With listbox.Items.IndexOf("abber")

That is:

int curIndex = listbox.Items.IndexOf("abber");
if(curIndex >= 0)
{
    MessageBox.Show(listbox.Items[curIndex].ToString());
}