指定Picturebox VB.net

Question

This is probably a very simple question, but I'm not sure how to phrase it. I'll just explain what I'm trying to do.

I've made a grid of PictureBoxes, and want to make ones light up when activated. They range from picturebox1 to picturebox200, and I have an integer specifying which one I want lit. How would I go about (in pseudocode):

Dim P as integer = 50

me.pictureboxP.image = my.resources.on

The only way I know at the moment is a massive select case quagmire.

Answer 1

Add them to an array. Then use the index to select which one you want.

Answer 2

You can do this by using the Controls.Find method of the Form. Something like the following should work:

Dim p as Integer = 50
Dim pic as PictureBox = Me.Controls.Find("picturebox" + p.ToString, True)
If Not pic Is Nothing Then
    pic.Image = My.Resources.Icon
End If

See also this question: How do I refer to a windows form control by name (C# / VB)

Answer 3

Controls.Find() returns an ARRAY of Control, even if there is only one match. Thus you need to check for any return values using the Length of the Array and then CAST the returned control to your desired type:

Dim p as Integer = 50
Dim matches() As Control = Me.Controls.Find("picturebox" + p.ToString, True)
If matches.Length > 0 AndAlso TypeOf matches(0) Is PictureBox Then
    Dim pic as PictureBox = DirectCast(matches(0), PictureBox)
    pic.Image = My.Resources.Icon
End If

Answer 4

1. Add the picture boxes to an array
2. Set tag property to True for 'ON' images and False for 'OFF' images

3. Then to select your ON pictures, just do the following and then highlight them as you wish

     MyArray.Select(function(x) x.Tag = True)