Can anyone write assembly code to copy a string?

[xiaoyao]

How to do pointers in Visual Basic - CodeProject
https://www.codeproject.com/Articles...n-Visual-Basic

Option Explicit
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Function GetProcessHeap Lib "kernel32" () As Long
Private Declare Function HeapAlloc Lib "kernel32" _
    (ByVal hHeap As Long, ByVal dwFlags As Long, _
    ByVal dwBytes As Long) As Long
Private Declare Function HeapFree Lib "kernel32" _
    (ByVal hHeap As Long, ByVal dwFlags As Long, _
    lpMem As Any) As Long
Private Declare Sub CopyMemoryPut Lib "kernel32" Alias _
    "RtlMoveMemory" (ByVal Destination As Long, _
    Source As Any, ByVal Length As Long)
Private Declare Sub CopyMemoryRead Lib "kernel32" Alias _
    "RtlMoveMemory" (Destination As Any, _
    ByVal Source As Long, ByVal Length As Long)

Dim pHead As Long
Private Type ListElement
    strData As String * 255 '==255 * 2=500 bytes  vbStrings are UNICODE !
    pNext As Long  '4 bytes
                'pointer to next ; ==0 if end of list
'----------------
'total: 504 bytes
End Type

Private Sub CreateLinkedList()
'add three items to list
' get the heap first
    Dim pFirst As Long, pSecond As Long 'local pointers
    Dim hHeap As Long
    hHeap = GetProcessHeap()
    'allocate memory for the first and second element
    pFirst = HeapAlloc(hHeap, 0, 504)
    pSecond = HeapAlloc(hHeap, 0, 504)
    If pFirst <> 0 And pSecond <> 0 Then
    'memory is allocated
        PutDataIntoStructure pFirst, "Hello", pSecond
        PutDataIntoStructure pSecond, "Pointers", 0
        pHead = pFirst
    End If
    'put he second element in the list
End Sub

Private Sub Command1_Click()
    CreateLinkedList
    ReadLinkedListDataAndFreeMemory
End Sub

Private Sub PutDataIntoStructure(ByVal ptr As Long, _
        szdata As String, ByVal ptrNext As Long)
Dim le As ListElement
    le.strData = szdata
    le.pNext = ptrNext
    CopyMemoryPut ptr, le, 504
End Sub

Private Sub ReadDataToStructure(ByVal ptr As Long, _
        struct As ListElement)
    Dim le As ListElement
    CopyMemoryRead le, ptr, 504
    struct.strData = le.strData
    struct.pNext = le.pNext
End Sub
'Private Sub ReadDataToStructure(ByVal ptr As Long, _
'        struct As ListElement) ' why it's err?
'    CopyMemoryRead struct, ptr, 504 ' why it's err?
'End Sub
Private Sub ReadLinkedListDataAndFreeMemory()
Dim pLocal As Long
Dim hHeap As Long
Dim le As ListElement
Dim strData As String
    pLocal = pHead
    hHeap = GetProcessHeap()
    Do While pLocal <> 0
        ReadDataToStructure pLocal, le
        strData = strData & vbCrLf & le.strData
        HeapFree hHeap, 0, pLocal
        pLocal = le.pNext
    Loop
    MsgBox strData
End Sub

Private Sub ReadDataToStructure(ByVal ptr As Long, _
struct As ListElement) ' why it's err?
CopyMemoryRead struct, ptr, 504 ' why it's err?
End Sub