C# Help With Removing Runtime Created TextBoxes

[wingers1290]

Hi, i am creating up to 10 textboxes using the following code:

if (textBoxIndex != 11)
            {
                TextBox field = new TextBox();
                field.Name = "field" + textBoxIndex.ToString();
                textBoxIndex++;
                field.Size = new Size(200, 20);
                panel1.Controls.Add(field);
            }
            else
            {
                MessageBox.Show("A Maximum of 10 Areas is Supported");
            }

What I need to do now is have a button that removes the text boxes from bottom to top, but there may not neccessarily be 10 textboxes present their may only be five for example and I need some help with this please.

[ddanbe]

Just as the panel1.Controls (wich is of type Control.ControlsCollection) has an Add method, it may not be to suprising to notice, it also has a Remove method.

[wingers1290]

yes i know that but how do i get it to remove the last one in the sequence and eventually through to the first

[ddanbe]

To remove the fifth control in your collection use:
panel1.Controls.RemoveAt(4);Use the Count method first to test how many controls are still in the collection.

[wingers1290]

Count method?

[ddanbe]

Yes, in case you don't know how many controls are in your collection, you use panel1.Controls.Count;
It would give errors if you removed the fifth control of a collection wich contains only three controls.
There is also the IndexOf method wich returns an integer you could use in the RemoveAt method.
Like in:
panel1.Controls.RemoveAt(IndexOf(field));

[wingers1290]

ok i see but if i pressed that again it wouldnt remove the text before that, say if i generated 3 textoxes the index would be at 3 and so the code you posted would remove textbox 3 but if i pressed it again it wouldnt remove text box 2 would it?

[ddanbe]

If you have three controls, the index of the last one is 2!
Remember: your indexes go from 0,1,2, the count is 3!

[wingers1290]

ive changed it so that it starts at one so the third textbox would have an index of 3!

[wingers1290]

oh i get it now, i used the following code to do it.

if (panel1.Controls.Count == 2)
            {
                panel1.Controls.RemoveAt(1);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 3)
            {
                panel1.Controls.RemoveAt(2);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 4)
            {
                panel1.Controls.RemoveAt(3);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 5)
            {
                panel1.Controls.RemoveAt(4);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 6)
            {
                panel1.Controls.RemoveAt(5);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 7)
            {
                panel1.Controls.RemoveAt(6);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 8)
            {
                panel1.Controls.RemoveAt(7);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 9)
            {
                panel1.Controls.RemoveAt(8);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 10)
            {
                panel1.Controls.RemoveAt(9);
                textBoxIndex = textBoxIndex - 1;
            }
            if (panel1.Controls.Count == 11)
            {
                panel1.Controls.RemoveAt(10);
                textBoxIndex = textBoxIndex - 1;
            }

thanks again!

[ddanbe]

Although your code will work as you want it.
I have a remark here:
Whenever you see a repetition like you have now, that must start ring a bell in your head:
*** Perhaps I could make a loop here?
*** Perhaps I better make a function?
*** Perhaps .NET has just the thing I need?

I would do it this way:

if (panel1.Controls.Count > 0) //check if I have controls in my collection
{
    panel1.Controls.RemoveAt( panel1.Controls.Count - 1 );
} //this will remove last control in the collection

[wingers1290]

thanks, i used this

if (textBoxIndex >= 1)
            {
                panel1.Controls.RemoveAt((textBoxIndex) - 1);
                textBoxIndex = textBoxIndex - 1;
            }
            else
            {

            }

thanks for your help

[ddanbe]

Fine. I'm glad I could help you out.:)