vb.net从sendmessagestring获取listview项目

Private Declare Function SendMessage Lib "user32.dll" Alias "SendMessageA" (ByVal hWnd As IntPtr, ByVal wMsg As Integer, ByVal wParam As Integer, ByVal lParam As IntPtr) As IntPtr
Private Function SendMessageString(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, ByRef lParam As String) As IntPtr
End Function
Public Const LB_GETCOUNT = &H18B
Public Const LB_GETTEXT = &H189
Public Const LB_GETTEXTLEN = &H18A

hwnd = FindWindow(vbNullString, "Virtual CDRom Control Panel")
x = FindWindowEx(hwnd, 0, vbNullString, "List1")

Dim listCount As String = SendMessage(x, LB_GETCOUNT, CLng(0), CLng(0))
Dim textLen As String = SendMessage(x, LB_GETTEXTLEN, 30, CLng(0))
Dim itemText As String = New String(" ", textLen)
Dim theText As String = SendMessageString(x, LB_GETTEXT, 30, itemText)

MessageBox.Show(theText)