Lets say you have lots of data your listview. Now you want to Group This data According to a Particular Subitem.

For Example:

Suppose i have some books data in my ListView.
this listview items contains Author name and Books Title.

And there are 2000 Books in list view.

Now i want to group the data in listview according to the Authors.

Now lets say there are 50 Unique Authors , meaning we will have to create 50 Groups in listview.

this seem hectic, and i don’t know if there is any inbuilt function to automatically group this items, but i have created mine To automatically do the above.

Hope it becomes useful to someone.

public void GroupListView(ListView lstV, int SubItemIndex) {
 bool flag = true;

 foreach(ListViewItem l in lstV.Items) {
  string strmyGroupname = l.SubItems[SubItemIndex].Text;

  foreach(ListViewGroup lvg in lstV.Groups) {
   if (lvg.Name == strmyGroupname) {
    l.Group = lvg;
    flag = false;
   }
  }

  if (flag == true) {
   ListViewGroup lstGrp = new ListViewGroup(strmyGroupname, strmyGroupname);
   lstV.Groups.Add(lstGrp);
   l.Group = lstGrp;
  }

  flag = true;
 }
}

How To Use The Code:
Lets say the author’s sub item’s index is 1 and listview name is LstBooks then call the function like:

GroupListView(LstBooks,1);

Vb.net Version:

Public Sub GroupListView(ByVal lstV As ListView, ByVal SubItemIndex As Int16)
Dim flag As Boolean = True
For Each l As ListViewItem In lstV.Items

Dim strmyGroupname As String = l.SubItems(SubItemIndex).Text

For Each lvg As ListViewGroup In lstV.Groups

If lvg.Name = strmyGroupname Then
l.Group = lvg
flag = False
End If

Next

If flag = True Then
Dim lstGrp As New ListViewGroup(strmyGroupname, strmyGroupname)
lstV.Groups.Add(lstGrp)
l.Group = lstGrp
End If

flag = True

Next
End Sub

Output:

Let’s say you have some invoice numbers which contains Alphabets as well as numeric number.
And you want to increment it one by one.
For Example:

if Invoice number is “AZ99999999” then Next Invoice Number will be “BA00000001”

Notice here that , the invoice number’s length is 10 Characters out of which first 2 are Alphabets and the rest (8) are Numeric. invoice number can be of any digit with any combination of numeric and alphabets.

The function can be changed to your need very easily. but here i will demonstrate for the above example.

Function:

Public Function IncrementInvoice(ByVal strInvoiceNumber As String) As String

If strInvoiceNumber.Length <> 10 Then
Return "Error"
End If

Dim strAlphaPart(1) As Char
strAlphaPart(0) = strInvoiceNumber(0)
strAlphaPart(1) = strInvoiceNumber(1)

Dim IntPart As Int64
IntPart = strInvoiceNumber.Substring(2, 8)
If IntPart = 99999999 Then
If strAlphaPart(1) = "Z" Then
strAlphaPart(0) = Chr(Asc(strAlphaPart(0)) + 1)
strAlphaPart(1) = "A"

IntPart = 1

Return strAlphaPart(0) & strAlphaPart(1) & IntPart.ToString.PadLeft(8, "0")
Else
strAlphaPart(1) = Chr(Asc(strAlphaPart(1)) + 1)
End If

Else
IntPart += 1
Return strAlphaPart(0) & strAlphaPart(1) & IntPart.ToString.PadLeft(8, "0")
End If

End Function

Output:

‘outputs example:
strTemp = IncrementInvoice(“AA99999998”) ‘Output will be: “AA99999999”
strTemp = IncrementInvoice(“AA00000005”) ‘Output will be: “AA00000006”
strTemp = IncrementInvoice(“AZ00000007”) ‘Output will be: “AZ00000008”
strTemp = IncrementInvoice(“AZ99999999”) ‘Output will be: “BA00000001”

1. Add List box on a Forms.
2. Now add a reference to System.Diagnostics

Code:

Process[] curProcesses = Process.GetProcesses();

foreach (Process p in curProcesses)
{
listBox1.Items.Add(p.ProcessName);
}

Output: