Referencing components with index

sysrev

If I'm in the wrong place or this is a stupid question I apologise in advance. I am having to write a data acquisition program in .NET (C#) before I’ve had time to learn it which is making for some interesting code. What I would really like to do is reference a group of 24 progress bar components within a for/next loop using the index of the loop. Does anyone know how to do this? The code I use at the moment is very inelegant and bugs me. Would appreciate any pointers (sorry ‘bout pun)

Ted Edwards

led mike

Wow Ted, that just sounds horrible. But given your situation:

sysrev wrote:

before I’ve had time to learn it

and

sysrev wrote:

a group of 24 progress bar components

With that situation I would go with "if it works, I don't care".

sysrev

But I'll need to do it again somewhere - and again, and again.........

Ted Edwards

Robert Rohde

Hi, hard to give a good answer without knowing your exact situation. You could add all progress bars to a List. After you have done this once you can iterate the list with for/foreach or whatever technique you like. Robert

sysrev

Thanks for the suggestion Robert. The progress bars display the output of a pressure sensor over a 24 hour period. When I get a new reading, I shift values chronologically "down" one bar and put the new value in the "top" (most recent) bar. The coding begs for an iterative loop but I don't know how to address the bars name property with the index. So I ended up using a switch construct which works okay but is awkward to maintain. The List class is new to me and on your suggestion I had a quick look at it. I must say, it does not look promising but will try it out if I can.

Ted

Robert Rohde

Hi, I'll try to outline what I meant:

//Field declaration in the Form/UserCotrol
private List _bars;

//somewhere after the InitializeComponents call
_bars = new List(new ProgressBar[] { pb1, pb2, pb3, ... });

//when you want to update the bars
for (int i = 0; i < 24; i++)
{
_bars[i] = someArrayWithTheValues[i];
}

With the mod operator you could also easily switch which hour should be displayed at the top: int hourToDisplayAtTop = 4;

for (int i = 0; i < 24; i++)
{
_bars[i] = someArrayWithTheValues[(i + hourToDisplayAtTop) % 24];
}

Robert

sysrev

I think I can see what you are suggesting and am trying to experiment with it in a new application as here: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; namespace IndexComponents { public partial class Form1 : Form { private ProgressBar pb1; private ProgressBar pb2; private ProgressBar pb3; private List _bars; public Form1() { InitializeComponent(); int[] someArrayWithTheValues = new int[3] { 1, 2, 3 }; //Field declaration in the Form/UserCotrol /// private List _bars; //somewhere after the InitializeComponents call /// _bars = new List(new ProgressBar[] { pb1, pb2, pb3 });//when you want to update the bars _bars = new List(new ProgressBar[] { pb1, pb2, pb3 });//when you want to update the bars for (int i = 0; i < 3; i++) { _bars[i] = someArrayWithTheValues[i]; } //With the mod operator you could also easily switch which hour should be displayed at the top: int hourToDisplayAtTop = 2; for (int i = 0; i < 3; i++) { _bars[i] = someArrayWithTheValues[(i + hourToDisplayAtTop) % 24]; } } } } I am now working on the last two(I hope!) build error which are flagged within the two for loops as below: Error 1 Cannot convert type 'int' to 'System.Windows.Forms.ProgressBar' Error 2 Cannot implicitly convert type 'int' to 'System.Windows.Forms.ProgressBar' Ted Edwards

Robert Rohde

Replace _bars[i] = ... with _bars[i].Value = ... (Sorry, my mistake) Robert

sysrev

That's great. It all works - I can experiment further now I have a working example. Thanks for your help.

Ted