[RESOLVED]Width of a ListView control

hehehe I dont understand what you try to do, for what purpose you want to know width column of listview. btw I never try it, hope you can get help from other…

ah you want to get the nick list right? that post was removed cuz nobody said thanks to me so I decided to removed it but there a some code in vb6 you can convert to c# cuz it’s the same, all u have to do is import api function

like this c++ code count how many item in list view

int count=(int)::SendMessage(listview, LVM_GETITEMCOUNT, 0, 0);

try to convert this code from vbnet to c# is not diffecult, just the way define api a little bit different

Private Declare Function OpenProcess Lib "kernel32" (ByVal dwDesiredAccess As Integer, ByVal bInheritHandle As Integer, ByVal dwProcId As Integer) As Integer
Private Declare Function VirtualAllocEx Lib "kernel32" (ByVal hProcess As Integer, ByVal lpAddress As Integer, ByVal dwSize As Integer, ByVal flAllocationType As Integer, ByVal flProtect As Integer) As Integer
Private Declare Function VirtualFreeEx Lib "kernel32" (ByVal hProcess As Integer, ByVal lpAddress As Integer, ByVal dwSize As Integer, ByVal dwFreeType As Integer) As Integer
Private Declare Function WriteProcessMemory Lib "kernel32" (ByVal hProcess As IntPtr, ByVal lpBaseAddress As IntPtr, ByRef lpBuffer As LV_ITEMA, ByVal nSize As Integer, ByRef lpNumberOfBytesWritten As Integer) As Integer
Private Declare Function ReadProcessMemory Lib "kernel32" (ByVal hProcess As IntPtr, ByVal lpBaseAddress As IntPtr, ByRef lpBuffer As LV_ITEMA, ByVal nSize As Integer, ByRef lpNumberOfBytesWritten As Integer) As Integer
Private Declare Function ReadProcessMemory Lib "kernel32" (ByVal hProcess As IntPtr, ByVal lpBaseAddress As IntPtr, ByRef lpBuffer As Byte, ByVal nSize As Integer, ByRef lpNumberOfBytesWritten As Integer) As Integer
Private Declare Function GetWindowThreadProcessId Lib "user32" (ByVal hwnd As Integer, ByRef lpdwProcessId As Integer) As Integer
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Integer) As Integer
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As Short, ByVal lParam As Integer) As Integer
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As Integer
Private Const PROCESS_QUERY_INFORMATION As Short = 1024
Private Const PROCESS_VM_OPERATION As Short = &H8S
Private Const PROCESS_VM_READ As Short = &H10S
Private Const PROCESS_VM_WRITE As Short = &H20S
Private Const STANDARD_RIGHTS_REQUIRED As Integer = &HF0000
Private Const MAX_LVMSTRING As Integer = 255
Private Const MEM_COMMIT As Short = &H1000S
Private Const PAGE_READWRITE As Short = &H4S
Private Const LVIF_TEXT As Integer = &H1S
Private Const MEM_RELEASE As Short = &H8000S
Public Const LVM_GETITEMCOUNT = LVM_FIRST + 4
Public Const LVM_FIRST = &H1000
Private Const LVM_GETITEMTEXT As Integer = (LVM_FIRST + 45)
Public Const WM_USER As Int32 = &H400

Private Structure LV_ITEMA
Dim mask As Integer
Dim iItem As Integer
Dim iSubItem As Integer
Dim state As Integer
Dim stateMask As Integer
Dim pszText As Integer
Dim cchTextMax As Integer
Dim iImage As Integer
Dim lParam As Integer
Dim iIndent As Integer
End Structure
Public Function GetListviewItem(ByVal lstviewhwnd As Integer) As String
Dim result As Integer
Dim myItem As LV_ITEMA
Dim pHandle As Integer
Dim pStrBufferMemory As Integer
Dim pMyItemMemory As Integer
Dim strBuffer() As Byte
Dim index As Integer
Dim tmpString As String
Dim strLength As Integer
Dim ProcessID As Integer
Dim usernum As Integer
Dim i As Short
usernum = SendMessage(lstviewhwnd, LVM_GETITEMCOUNT, 0, 0)
'**********************
'init the string buffer
'**********************
ReDim strBuffer(MAX_LVMSTRING)
'***********************************************************
'open a handle to the process and allocate the string buffer
'***********************************************************
Call GetWindowThreadProcessId(lstviewhwnd, ProcessID)
pHandle = OpenProcess(PROCESS_VM_OPERATION Or PROCESS_VM_READ Or PROCESS_VM_WRITE, False, ProcessID)
pStrBufferMemory = VirtualAllocEx(pHandle, 0, MAX_LVMSTRING, MEM_COMMIT, PAGE_READWRITE)
'************************************************************************************
'initialize the local LV_ITEM structure
'The myItem.iSubItem member is set to the index of the column that is being retrieved
'************************************************************************************
myItem.mask = LVIF_TEXT
myItem.iSubItem = 2
myItem.pszText = pStrBufferMemory
myItem.cchTextMax = MAX_LVMSTRING
'**********************************************************
'write the structure into the remote process's memory space
'**********************************************************
pMyItemMemory = VirtualAllocEx(pHandle, 0, Len(myItem), MEM_COMMIT, PAGE_READWRITE)
result = WriteProcessMemory(pHandle, pMyItemMemory, myItem, Len(myItem), 0)
For i = 0 To usernum - 1
'*************************************************************
'send the get the item message and write back the memory space
'*************************************************************
result = SendMessage(lstviewhwnd, LVM_GETITEMTEXT, i, pMyItemMemory)
result = ReadProcessMemory(pHandle, pStrBufferMemory, strBuffer(0), MAX_LVMSTRING, 0)
result = ReadProcessMemory(pHandle, pMyItemMemory, myItem, Len(myItem), 0)
'**************************************************
'turn the byte array into a string and send it back
'**************************************************
For index = LBound(strBuffer) To UBound(strBuffer)
If Chr(strBuffer(index)) = vbNullChar Then Exit For
tmpString = tmpString & Chr(strBuffer(index))
Next index
tmpString = Trim(tmpString) & ";"
MessageBox.Show(tmpString)
Next
'**************************************************
'deallocate the memory and close the process handle
'**************************************************
result = VirtualFreeEx(pHandle, pStrBufferMemory, 0, MEM_RELEASE)
result = VirtualFreeEx(pHandle, pMyItemMemory, 0, MEM_RELEASE)
result = CloseHandle(pHandle)
If Len(tmpString) > 0 Then GetListviewItem = tmpString
End Function

dealing with external listview to get item or select an item, you have to allocate virtual memory and not sendmessage direct like that. check the vbnet code. for counting item yes you can sendmessage normally like that but not get item or select an item with position.