Dim TxtLineStr() As String
Dim i As Long
Open "d:\1.txt" For Input As #1
    Do While Not EOF(1)
        ReDim Preserve TxtLineStr(i) As String
        Line Input #1, TxtLineStr(i)
        'if TxtLineStr(i)="http://" then TxtLineStr(i)="
http://www.baidu.com"
        i = i + 1
    Loop
Close #1
TxtLineStr(1) = "
http://www.baidu.com"
Open "d:\1.txt" For Output As #1
    For i = 0 To UBound(TxtLineStr)
        Print #1, TxtLineStr(i)
    Next
Close #1