C# - Combobox index change after editing

Question

A moment ago someone answered my question on how to edit the combobox loaded with a text file, and how to save the recently edited line.

C#: Real-time combobox updating

The problem now is that I can only change one letter before it updates, and then the selectedindex changes to -1, so I have to select the line I was editing again in the dropdown list.

Hopefully someone knows why it's changing index, and how to stop it from doing that.

We can't see the prev answer here or how you implemented that. Please update the previous question. Voting to close. — H H, Sep 20 '10 at 13:00
possible duplicate of [C#: Real-time combobox updating](http://stackoverflow.com/questions/3750990/c-real-time-combobox-updating) — H H, Sep 20 '10 at 13:01
may be it's changing index because it checks if items[selectedIndex] equal comboBox1.Text and returns -1 if not. — SKINDER, Sep 20 '10 at 14:39

score 4 · Answer 1 · answered Sep 20 '10 at 14:15

As my understanding of the problem goes, you can do one thing. In the comboBox1_TextChanged method, instead of putting the previous code, you can just set a bool variable, say textChangedFlag to true and you can set the default value of this variable as false. And then use KeyDown event to edit the combobox item. I will give a sample code.

Sample Code:

if (e.KeyCode == Keys.Enter)
        {
            if (textChangedFlag )
            {
                if(comboBox1.SelectedIndex>=0)
                {
                    int index = comboBox1.SelectedIndex;
                    comboBox1.Items[index] = comboBox1.Text;
                    textChangedFlag = false;
                }

            }
        }

You can put this code in KeyDown event handler method. Hope it helps

Thank you for the code, I cant test it untill tomorrow so I'll let you know. — Nick, Sep 21 '10 at 06:31

score 3 · Accepted Answer · answered Sep 20 '10 at 14:19

private int currentIndex;

public Form1()
{
    InitializeComponent();

    comboBox1.SelectedIndexChanged += RememberSelectedIndex;
    comboBox1.KeyDown += UpdateList;
}

private void RememberSelectedIndex(object sender, EventArgs e)
{
    currentIndex = comboBox1.SelectedIndex;
}

private void UpdateList(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.Enter && currentIndex >= 0)
    {
        comboBox1.Items[currentIndex] = comboBox1.Text;
    }
}

Thank you, the other code might have worked too, but this one seemed a little more flexible to me. — Nick, Sep 22 '10 at 06:23

C# - Combobox index change after editing

2 Answers2