VB如何提取htm代码中固定的字符串

       Private Sub Command1_Click()

       Dim TempLine As String

       Dim StartPos As Long, EndPos As Long

       Open "D:\a.txt" For Input As #1

        Do While Not EOF(1)

        Line Input #1, TempLine

        StartPos = InStr(TempLine, "http")

        If StartPos > 0 Then

        EndPos = InStr(StartPos, TempLine, ",")

        If EndPos > 0 Then

        EndPos = InStr(EndPos + 1, TempLine, ",")

        If EndPos > 0 Then

        List1.AddItem Mid(TempLine, StartPos, EndPos - StartPos - 1)

        End If

        End If

        End If

        Loop

       Close #1

       End Sub