C# Winforms - Trouble with IF statements

Question

Here's what I'm trying to do. I have a form with several checkboxes. The user will check 1 or 2 or 12 of them, and then click a button and then several things will happen, depending on which boxes were checked.

    private void checkBox1_CheckedChanged(object sender, EventArgs e)
    {
        if (checkBox1.Checked == true)
        {
            checkBox1.Tag = "IP";
            Console.WriteLine(checkBox1.Tag);
        }
        else
        {
            checkBox1.Tag = null;
        }
    }
    private void CheckBox2_CheckedChanged(object sender, EventArgs e)
    {
        if (checkBox2.Checked == true)
        {
            checkBox2.Tag = "PR";
            Console.WriteLine(checkBox2.Tag);
        }
        else
        {
            checkBox2.Tag = null;

        }
    }

So that's just a sample of the code for 2 of the 24 checkboxes I have on this form. Once the user clicks the button, the form will save a file using the checkboxX.Tag variable:

        private void button2_Click(object sender, EventArgs e)
    {

        if (string.IsNullOrWhiteSpace(myFile) &
            string.IsNullOrWhiteSpace(selectDate) &
            string.IsNullOrWhiteSpace(selectDept))
        {
            MessageBox.Show("Well, that didn't work. Check your info and try again!");
            return;
        }
        else File.Exists(myFile);
        {
            MessageBox.Show("Document(s) added! " + selectDept + selectWorker +
              " for " + dateTime.Year + "-" + dateTime.Month + "-" + dateTime.Day);
            MessageBox.Show("To add more docs, re-open this program");
            if (checkBox1.Checked)
            {
                string finalName = @"C:\testing\" + selectDept + selectWorker + @"\" + 
                  checkBox1.Tag + dateTime.Year + dateTime.Month + dateTime.Day + ".pdf";
                textBox2.Text = finalName;
                File.Copy(myFile, finalName, true);
            }
            if (checkBox2.Checked)
            {
                string finalName = @"C:\testing\" + selectDept + selectWorker + @"\" + 
                  checkBox2.Tag + dateTime.Year + dateTime.Month + dateTime.Day + ".pdf";
                textBox2.Text = finalName;
                File.Copy(myFile, finalName, true);
            }

So, as it stands, it works for the first and only the first checkbox. Like, the file will copied and saved just like it's supposed to, but instead of having 5 identical files named "IP20181012", "PR20181012", "FS20181012" and so on, I end up with one file named "IP20181012", and then one other file just named "20181012", making me believe that the checkBox2.Tag variable is never set. I've tried using a separate variable (other than the built-in checkBox1.Tag one), and the exact same problem happens. It seems like only checkBox1.Tag will get set properly while the other checkBoxX.Tag variables all stay null. Even when I declared separate varaibles and then tried to set them in the checkboxes, only the one for checkBox1 will ever be set, no matter what I do.

Also, is this an okay way to use if statements? I don't need them nested. Can I just kinda line them up so that clicking the button will just run through all of the if statements underneath it?

Answer 1

A bunch of if statements in the button's click handler is a good way to do it. And you won't even need to use the Tag property or handle the checkbox checked events anymore because you are checking the checked property anyway.

    if (checkBox1.Checked)
    {
        string finalName = @"C:\testing\" + selectDept + selectWorker + @"\IP"
            + dateTime.Year + dateTime.Month + dateTime.Day + ".pdf";
        textBox2.Text = finalName;
        File.Copy(myFile, finalName, true);
    }
    if (checkBox2.Checked)
    {
        string finalName = @"C:\testing\" + selectDept + selectWorker + @"\PR"
          + dateTime.Year + dateTime.Month + dateTime.Day + ".pdf";
        textBox2.Text = finalName;
        File.Copy(myFile, finalName, true);
    }

Answer 2

How did you create the event handlers for these checkboxes?

Did you double-click on each checkbox?

Or did you double-click on one, create the event handler, and then copy-and-change that one for each of the others?

What happens that you can't see is that in the code-behind file (MyForm.Designer.cs), there's a line for each event handler that looks like this:

this.checkBox1.CheckedChanged += new System.EventHandler(this.checkBox1_CheckedChanged);

That's the line that actually wires up the event. Without that line, your checkbox isn't actually going to respond to anything.

If you started in VB6 or VBA, then it's a bit confusing because in those languages, just creating a method with the right name would magically cause this wiring-up to happen. But in C# (and VB .NET) it's explicit, even though it may be hidden in the Designer file.

But you can also add these lines yourself. This is the way I always do it, so the Designer isn't hiding things. In the constructor of your form, you can type them this way:

public MyForm()
{
    checkBox1.Checked += checkBox1_Checked;
    checkBox2.Checked += checkBox2_Checked;
    [etc.]
}

Answer 3

Coding a cleaner code will make things easier. Some suggestions:

1. Instead of directly using your checkboxes, create a Class ("CheckBoxConfigs.cs" that will have boolean/string flags regarding the checkbox functionality (your code will be easier to read/mantain);

2. Make all your checkboxes use the same handler (the same "event" function), where you can setup your "CheckBoxConfigs.cs" flags (instead of using "tag" property you would have a class with the role to handle the flags) instead of creating code for 24 CheckBox_CheckedChanged functions;

Answer 4

First set the Tag property for each checkbox in the designer to the strings you want. Then, get rid of the CheckChanged handlers. Finally, do something like this in you button handler (I've made obvious modifications (like I don't call File.Copy)):

 private void button2_Click(object sender, EventArgs e)
 {
     var selectDept = "MyDept";
     var selectWork = "MyWork";
     var myFile = @"c:\somefolder\somefile.ext";
     var dateTime = DateTime.Now;

     var formattedDate1 = dateTime.ToString("yyyy-MM-dd");
     var formattedDate2 = dateTime.ToString("yyyyMMdd");
     MessageBox.Show($"Document(s) added {selectDept}{selectWork} for {formattedDate1}");
     var checkboxes = new[]
     {
         checkBox1,
         checkBox2,
         checkBox3,
         //you get the idea
     };
     foreach (var checkbox in checkboxes)
     {
         if (checkbox.Checked)
         {
             var finalName = $@"C:\testing\{selectDept}{selectWork}\{checkbox.Tag}{formattedDate2}.pdf";
             textBox1.Text = finalName;      //no sure what this is for
             Debug.WriteLine($"MyFile: [{myFile}], Final Name: [{finalName}]");
         }
     }
 }

If I check the first and third checkboxes (whose Tag properties are "CK1" and "CK2", I get the following in my output:

MyFile: [c:\somefolder\somefile.ext], Final Name: [C:\testing\MyDeptMyWork\CK120181105.pdf]
MyFile: [c:\somefolder\somefile.ext], Final Name: [C:\testing\MyDeptMyWork\CK320181105.pdf]

I think that's pretty close to what you want