Public Function DeleteString(ByVal sString As String, ByVal PosComienzo As Long, ByVal Longitud As Long) As String

Public Function DeleteString7913(ByVal sString As String, ByVal PosComienzo As Long, ByVal Longitud As Long) As String
    DeleteString7913 = LeftB$(sString, PosComienzo + PosComienzo) & RightB$(sString, LenB(sString) - (PosComienzo + PosComienzo + Longitud + Longitud))
End Function
 

 
Option Explicit
 
Private Declare Sub RtlMoveMemory Lib "kernel32" (ByVal pDst As Any, ByVal pSrc As Any, ByVal ByteLen As Long)
Private Declare Sub PutMem4 Lib "msvbvm60" (ByVal Addr As Long, ByVal NewVal As Long)
Private Declare Sub PutMem2 Lib "msvbvm60" (ByVal Addr As Long, ByVal NewVal As Integer)
Private Declare Sub GetMem4 Lib "msvbvm60" (ByVal Addr As Long, ByVal RetVal As Long)
 
Public Function DeleteString_BZX(ByVal sString As String, ByVal lPosIni As Long, ByVal lSize As Long) As String
Dim lLnb    As Long
Dim lpStr   As Long
 
    If ((lSize Or lPosIni) And &H80000000) Then Exit Function
    lLnb = LenB(sString)
    if (lLnb = &H0) then exit function
    lSize = (lSize + lSize)
    lPosIni = (lPosIni + lPosIni)
 
    If (lPosIni >= lLnb) Then Exit Function
    lpStr = (lPosIni + lSize)
 
    If (lpStr > lLnb) Then
        lSize = (lLnb - lPosIni)
    End If
 
    GetMem4 VarPtr(sString), VarPtr(lpStr)
 
    If (lSize > &H0) Then
        lLnb = (lLnb - lSize)
        If (lLnb > lPosIni) Then
            RtlMoveMemory (lPosIni + lpStr), ((lPosIni + lpStr) + lSize), (lLnb - lPosIni)
            'MidB$(sString, (lPosIni + 1), (lLnb - lPosIni)) = MidB$(sString, (lPosIni + lSize + 1), (lLnb - lPosIni))
        End If
    End If
 
    PutMem2 ByVal (lpStr + lLnb), &H0
    PutMem4 ByVal (lpStr - &H4), lLnb
    PutMem4 VarPtr(DeleteString_BZX), lpStr
    PutMem4 VarPtr(sString), &H0
End Function
 
 

 
Private Sub Form_Load()
    Debug.Print DeleteString_BZX("BlackZeroX", -1, 4), Len(DeleteString_BZX("BlackZeroX", -1, 4))
    Debug.Print DeleteString_BZX("BlackZeroX", 9, 4), Len(DeleteString_BZX("BlackZeroX", 9, 4))
    Debug.Print DeleteString_BZX("BlackZeroX", 0, -4), Len(DeleteString_BZX("BlackZeroX", 0, -4))
    Debug.Print DeleteString_BZX("BlackZeroX", 1, 4), Len(DeleteString_BZX("BlackZeroX", 1, 4))
    Debug.Print DeleteString_BZX("BlackZeroX", 0, 4), Len(DeleteString_BZX("BlackZeroX", 0, 4))
    Debug.Print DeleteString_BZX("BlackZeroX", 0, 400), Len(DeleteString_BZX("BlackZeroX", 0, 400))
End Sub
 
 

Cita de: Psyke1 en 21 Octubre 2011, 10:18

Vale todo el más rápido gana.

Option Explicit
Private Declare Sub RtlMoveMemory Lib "kernel32" (ByVal pDst As Long, ByVal pSrc As Long, ByVal ByteLen As Long)
Private Declare Function SysAllocStringByteLen Lib "oleaut32.dll" (ByVal oleStr As Long, ByVal BLen As Long) As Long
 
Public Static Function RemoveStr_Psyke1(ByVal sText As String, ByVal lPosIni As Long, ByVal lLen As Long) As String
Dim lLenB                                   As Long
Dim lpString                                As Long
 
    lLenB = LenB(sText)
    If lLenB Then
        If (lPosIni Or lLen) And &H80000000 Then Exit Function
 
        lLen = (lLen + lLen)
        lPosIni = (lPosIni + lPosIni)
 
        If (lPosIni + lLen) = lLenB Then lLen = lLenB
 
        If (lLen = lLenB) And (lPosIni = 0&) Then
            RemoveStr_Psyke1 = sText
            Exit Function
        End If
 
        lpString = StrPtr(sText)
 
        RtlMoveMemory (lpString + lPosIni), (lpString + lPosIni + lLen), (lLenB - lPosIni + lLen)
        RtlMoveMemory VarPtr(RemoveStr_Psyke1), VarPtr(SysAllocStringByteLen(lpString, lLenB - lLen)), 4&
    End If
End Function
 
Private Sub Form_Load()
    MsgBox RemoveStr_Psyke1("hola amigo 123456789", 4, 6)
End Sub