How do I specify alternate rules for numericupdown control in VB.NET 14?

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I am working on a project that requires several NumericUpDown controls. Some of them change according to the values of others. For example, when nud1 value increases, nud2 value increases as well. But, if nud2 increases, nud1 stays the same. I would add code, but I cannot figure out how to do it at all! Can someone help me?

So, I have 8 NumericUpDown controls on the page. nud1 and nud5 are connected, nud3 and nud6 and nud7 are connected, and nud4 and nud8 are connected. When the first of these NUDs increases or decreases, their counterpart also increases or decreases. However, if the second NUD is increased/decreased, the first one should not change.

I need to know how to separate the UpButton method from the DownButton method. However, I cannot figure out how to utilize it. Help?

Kat

What I have tried:

I haven't been able to try anything. Every time I select or type the words "UpButton" or "DownButton", I get red squiggly lines and an error that states "UpButton is not declared. It may be inaccessible due to its protection level." I have tried to invoke it with "nudST.UpButton()"...that's about all I can think to do and it doesn't do anything except give me that little message.

Posted 18-Aug-16 21:57pm

PoiJoy

Updated 19-Aug-16 1:33am

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Richard MacCutchan 19-Aug-16 5:08am

You should probably use one of the events that signals when the value changes and modify the connected controls as necessary.

PoiJoy 19-Aug-16 5:11am

That's just it...WHAT events and WHAT connected controls? I've never used a NumericUpDown control before, but they're very popular, so I want to know HOW to use them...but I can't seem to find anything online about this control that makes sense.

Richard MacCutchan 19-Aug-16 5:31am

It's all in the documentation: https://msdn.microsoft.com/en-us/library/system.windows.forms.numericupdown(v=vs.110).aspx.

PoiJoy 19-Aug-16 5:34am

I apparently don't seem to be conveying my problem correctly. I don't know how to read MSDN's "information." I don't know how or where to put whatever code is listed on their site. I'm new to this and reading that site information is like trying to read Greek.

Richard MacCutchan 19-Aug-16 5:38am

Then you need to go and look for samples and tutorials. See https://www.google.com/search?q=how+to+use+numeric+up+down for some useful links.

BTW if you really cannot understand the MSDN documentation you are going to have a lot of problems as a developer.

PoiJoy 19-Aug-16 5:45am

I'm already having problems and suffering from severe depression because of it, but thank you for pointing that out.

Here's my problem with MSDN. They give you pieces of things, but don't really show you the whole picture. Yeah, intellectual property protection and all that, whatever. For someone trying to LEARN something, it's difficult to understand, for example, what this means:

Public Class NumericUpDown
Inherits UpDownBase
Implements ISupportInitialize
...okay. So...what? How does that make the buttons work differently than they're designed to? Or what does this block of code do? Why didn't it work when I tried it? Like I said, I'm new and I don't understand some of this stuff. I went to college for 4 years for this stuff, but I didn't learn very much about actual coding. For some reason, that wasn't the main focus of my programming courses. They only seemed to teach me how to write simple methods and set properties of my controls. Anything behind the scenes was simply left out of the curriculum.

Richard MacCutchan 19-Aug-16 6:10am

MSDN is a reference, where you can check the specific details of any control, method, event, function etc. But you need to understand the language (C,C++,C#, VB.NET etc.), and the .NET framework first. And for that you need training or long periods of self study. I find it difficult to believe that 4 years at college has not given you a better grounding in these subjects.

However, having said all that you can easily set up an event handler in Visual Studio. Go to the properties page of the control you are interested in and click the events list. Scroll down to ValueChanged and double click it. It will automatically add an event handler to your code so you can add whatever handling you need inside that method. It would probably help you to create a simple project with two such controls to play around with just to see what you need to do.

And on a final note, don't use the default names (nud1, nud2 etc) for controls, use proper meaningful names that give an idea what the control is for. You may know what nud8 does today but in 6 months time you will probably have forgotten. And worse still for someone else who has the job of maintaining your code.

PoiJoy 19-Aug-16 14:32pm

Thank you for understanding. My professors had a tendency to assume that everyone in their class was already a pro, which is ridiculous. For the most part, I understand VB.NET, but in school, they never once actually did anything to change the behavior of an established control. If it was a button, it had a click event. If it was a drop-down, it had an index changed event...and so on. So, back to the question here, how do I utilize the UpButton/DownButton methods in VB for these controls? Part of the problem is that the two connected NUDs aren't always going to be the same value. If nud1 goes up/down, nud2 should follow suit, but not the other way around. (I am only using "nud1" and "nud2" as examples. The actual controls are called nudST and nudHP.) So, I need to be able to differentiate between increases and decreases in the values.
I have gotten the program to work using buttons and a textbox, but I want to know how the NumericUpDown control works and how to utilize it's methods and properties and such. As I've got to teach myself how to use VS Community 2015, I need to know how to use things they didn't have in VS 2008...at least we didn't USE them in class.

Richard MacCutchan 20-Aug-16 3:47am

You don't utilise those methods, you use an event handler which gets fired every time the value changes. See my suggested solution below. I know it's C# but it should be easy to convert to VB.NET

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Richard MacCutchan · Answer 1 · 2016-08-19T01:33:00

Further to my suggestion above to create a simple application. Create a form with two updown controls and a text box. Make sure the names match those used in the following code sample. Add the method name numericUpDown_ValueChanged to the ValueChanged event of both controls and the code below to your main form code.

C#

private void numericUpDown_ValueChanged(object sender, EventArgs e)
{
    if (sender == numericUpDown1)
    {
        // if control 1 changes then copy its value to control 2
        numericUpDown2.Value = numericUpDown1.Value;
    }

    // write a message to the textbox showing both values
    StringBuilder sb = new StringBuilder();
    sb.Append("NUD1: ");
    sb.Append(numericUpDown1.Value.ToString());
    sb.Append(", NUD2: ");
    sb.Append(numericUpDown2.Value.ToString());
    textBox1.Text = sb.ToString();
}

Play around with the code and the values as necessary.

How do I specify alternate rules for numericupdown control in VB.NET 14?

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How do I specify alternate rules for numericupdown control in VB.NET 14?

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