C# - Listbox Remove part of line

Question

I have a listbox that has contents that look like this:

C44     EXCLUDES    237.910  193.469  0    0603_5    
C45     EXCLUDES    244.102  193.387  0    0603_5    
R47     EXCLUDES    226.935  179.519  90   0402_2    
C18     CAP-00129G  230.960  190.619  0    0402_4    
C17     CAP-00129G  250.085  198.569  90   0402_3     
C25     CAP-00130G  255.635  189.669  90   0402_3    
C56     EXCLUDES    229.430  189.374  0    0402_4    
R42     EXCLUDES    241.010  192.194  90   TANT3216  
R10     EXCLUDES    246.560  203.894  0    0402_9    

On the click of a button, I would like to "REMOVE ENDINGS" and re-upload it to the ListBox. So the new ListBox would look like this:

C44     EXCLUDES    237.910  193.469  0 
C45     EXCLUDES    244.102  193.387  0
R47     EXCLUDES    226.935  179.519  90
C18     CAP-00129G  230.960  190.619  0
C17     CAP-00129G  250.085  198.569  90
C25     CAP-00130G  255.635  189.669  90
C56     EXCLUDES    229.430  189.374  0
R42     EXCLUDES    241.010  192.194  90
R10     EXCLUDES    246.560  203.894  0

All of the possibly endings are in this REGEX: Regex placementOneRegex = new Regex(@"(RES|0402|0201|0603|0805|1206|1306|1608|3216|2551|1913|1313|2513|5125|2525|5619|3813|1508|6431|2512|1505|2208|1005|1010|2010|0505|0705|1020|1812|2225|5764|4532|1210|0816|0363|SOT)");

CODE:

    private void removeEndingsButton_Click(object sender, EventArgs e)
    {
        string[] items;
        System.Windows.Forms.ListBox.ObjectCollection contents = placementOneListBox.Items;

        foreach (string str in contents)
        {
            Regex placementOneRegex = new Regex(@"(RES|0402|0201|0603|0805|1206|1306|1608|3216|2551"
                + @"|1913|1313|2513|5125|2525|5619|3813|1508|6431|2512|1505|2208|1005|1010|2010|0505|0705"
                + @"|1020|1812|2225|5764|4532|1210|0816|0363|SOT)");
            items = str.Split(' ');
            items[5].Replace(placementOneRegex.ToString(), "");
            placementOneListBox.Items.Equals(items);
        }

As you can probably tell.. this is not the best away to go about it. I think it would be easiest to string.Split() and then just join all the split's except the split[5]... except I do not know how to go about doing this..

• My code does not work

---

QUESTIONS:

• How do I grab each line in the listbox and remove the last piece of data (using string.Split())?
• Is there an easier way to do this?

Answer 1

    private void removeEndingsButton_Click(object sender, EventArgs e)
    {
        string[] items;
        char[] splitChars = new char[] {'\t', ' '};
        int fieldCount;
        int lineCount = 0;

        System.Windows.Forms.ListBox.ObjectCollection contents = placementOneListBox.Items;

        foreach (string str in contents)
        {
           lineCount++;
           items = str.Split(splitChars, StringSplitOptions.RemoveEmptyEntries);
           fieldCount = items.Length;
           placementOneListBox.Items[lineCount] = string.Join(" ", items.Take(fieldCount - 1).ToArray());
        }
    }

Answer 2

Looking at your data I'm thinking that you could use a string position to remove the endings. It looks like you want to truncate each entry after the 33rd position.

Are all the lines in this format?

Answer 3

Not perfect, but it does what you are looking for essentially. You have to tweak the Join to make it output how you want.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void Remove_Click(object sender, EventArgs e)
    {
        ListBox.ObjectCollection collection = placementOneListBox.Items;
        // New collection to store our modified data
        List<string> newCollection = new List<string>();
        // We need regex to account for 0 or more spaces between items in the array.
        Regex r = new Regex(" +");

        foreach (string item in collection)
        {
            // use the regex we created to split the item into an array, it splits it based on any number of spaces.
            string[] splitItem = r.Split(item);
            // We had to write an extension method that "removes" at a particular index.
            splitItem = splitItem.RemoveAt(5);
            // Put it back together again. might have to mess with this to make it output correctly
            string updatedItem = String.Join("    ", splitItem);
            // add new item to collection
            newCollection.Add(updatedItem);
        }
        // clear the existing stuff in the listbox collection
        placementOneListBox.Items.Clear();
        // we can use a List<T> as a data source so that's what were doing here.
        placementOneListBox.DataSource = newCollection;
    }


}

EDIT: Put this code in it's own class as is.

public static class ExtensionMethods
{
    // An extension method to remove an index from an array, it works with any value type
    public static T[] RemoveAt<T>(this T[] source, int index)
    {
        if (source == null)
            throw new ArgumentNullException();

        if (index < 0 || index > source.Length)
            throw new IndexOutOfRangeException();

        T[] dest = new T[source.Length - 1];

        if (index != 0)
            Array.Copy(source, 0, dest, 0, index - 1);

        if (index != source.Length)
            Array.Copy(source, index + 1, dest, index, source.Length - index - 1);

        return dest;
    }
}

EDIT: Don't use my previous one, I had to fix the extension method, it wasn't working when the specified index to be removed was 0 or the length of the array.

Answer 4

Will something like this work? I didn't test it.

private void removeEndingsButton_Click(object sender, EventArgs e)
{
    string[] items;
    System.Windows.Forms.ListBox.ObjectCollection contents = placementOneListBox.Items;

    foreach (string str in contents)
    {

       List<string> list = str.Split(' ').ToList();
       if(list.Count == 6)
       {
           string remove = list[5];
           list.Remove(remove);           
           placementOneListBox.Items.Equals(list.ToArray());
       }
    }
}

if those are tabs you might want to try '\t' in the split method.