VB.NET按字节截取字符串

代码实现从字符串左端开始按字节截取字符串（从右端或指定位置开始按字节截取的代码可以参考以下代码自行修改）

Private Function SubChar(ByVal s As String, ByVal CharCount As Integer) As String
Dim strRtn As String
Dim bytArray() As Byte
Dim chrArray() As Char
Dim intI As Integer
bytArray = System.Text.Encoding.Default.GetBytes(s)
If CharCount > System.Text.Encoding.Default.GetCharCount(bytArray) Then
strRtn = s
Else
chrArray = System.Text.Encoding.Default.GetChars(bytArray, 0, CharCount)
For intI = 0 To chrArray.Length - 1
strRtn = strRtn & chrArray(intI)
Next
End If
Return strRtn
End Function