VB的字符串缓冲类，为了回答一个问题匆忙写的，HoHo

VB的字符串缓冲类，为了回答一个问题匆忙写的，HoHo

VB的字符串缓冲类，为了回答一个问题匆忙写的，HoHo Option Explicit

Private mlngCapacity As Long '缓冲区的当前容量,可用于插入新的字符的存储空间

Private mlngLength As Long '字符个数

Private mlngEOA As Long '数组第一个空元素的索引

Private mabyt() As Byte

Private mlngUb As Long '数组上界

Private Sub Class_Initialize()

mlngCapacity = 2048

ReDim mabyt(4095)

End Sub

Private Sub Class_Terminate()

Erase mabyt

End Sub

Public Sub append(ByVal str As String)

Dim abyt() As Byte '添加的字符串转为Byte数组

Dim lngUb As Long '添加的字符串转为Byte数组的上界

Dim lngLength As Long '添加的字符串的长度

Dim i As Long

abyt = str

lngUb = UBound(abyt)

lngLength = (lngUb + 1) \ 2

Do While lngLength > mlngCapacity '插入新的字符超出缓冲区容量

mlngUb = mlngUb + 4096

ReDim mabyt(mlngUb) '缓冲区扩容

mlngCapacity = mlngCapacity + 2048

Loop

For i = 0 To lngUb

mabyt(mlngEOA + i) = abyt(i)

Next

mlngEOA = mlngEOA + lngUb + 1

mlngCapacity = mlngCapacity - lngLength

mlngLength = mlngLength + lngLength

Erase abyt

End Sub

Public Property Get length() As Long

length = mlngLength

End Property

Public Property Get capacity() As Long

capacity = mlngCapacity

End Property

Public Function toString() As String

ReDim Preserve mabyt(mlngEOA - 1)

toString = mabyt

ReDim Preserve mabyt(mlngUb)

End Function