有没有人调用过IC卡（Mifare）的各种标准动态函数，或者对DLL文件各种参数的使用很熟的，很急啊，愿意拿出500作为交流

[haj77]

有用c++build写的DLL, 由于第一次使用VB， 对DLL上面的参数在VB中重新定义不熟悉，
比喻unsigned char * 在VB中是定义成byref a() as byte 还是Byval a as string 拿不定主意，并且好像都可以！！ DLL文件主要是IC卡上面的标准调用，象Request、Anticoll、select、Read等等依此函数，本人愿意高分拿出交流，如果做过ic卡或对DLL相当熟悉的，留下Email, 解答问题愿意给高分.

[zhp80]

byref a() as byte or Byval a as string 是都可以，不过在VB中用Byval a as string 更符合VB的Style,因为string是BSTR,VB中的字符串都是BSTR，用Byval a as string 多数情况下操作会简单一些的；
但VB中字符都是DBCS的，因此在做一些底层的操作试会又麻烦，所以有时用byref a() as byte 写起来既丢失了VB的建议性，又不像c/c++的指针那样流畅，但不会为一些莫名其妙的问题去排错
我在做通讯时都用a() as byte

[of123]

都可以。不过当a的值不是字符时，最好用byref a() as byte，否则中文VB会自动处理字符串，弄成无法复原的乱码。

Declare Function RFMifare_Request Lib "advic32.dll" (ByVal mode As Long, cardtype As Long) As Long
Declare Function RFMifare_AntiColl Lib "advic32.dll" (CardSnr As Long) As Long
Declare Function RFMifare_Select Lib "advic32.dll" (ByVal CardSnr As Long) As Long
Declare Function RFMifare_LoadKey Lib "advic32.dll" (ByVal mode As Long, ByVal sector As Long, key As Byte) As Long
Declare Function RFMifare_Authentication Lib "advic32.dll" (ByVal mode As Long, ByVal sector As Long, ByVal blockno As Long) As Long
Declare Function RFMifare_Read Lib "advic32.dll" (ByVal blockno As Long, ReadBuff As Byte) As Long

例子：
status = RFMifare_Request(1, cdtype)
If status = 0 Then
If cdtype <> 4 And cdtype <> 16 Then
MsgBox "非门禁用卡！"
Exit Sub
End If
Else
StatusBar1.Panels(3) = " 呼叫失败"
Exit Sub
End If

status = RFMifare_AntiColl(cdsnr)
If status <> 0 Then
StatusBar1.Panels(3) = "防碰撞选择失败"
Exit Sub
End If

status = RFMifare_Select(cdsnr)
If status <> 0 Then
StatusBar1.Panels(3) = " 卡激活失败"
Exit Sub
End If


status = RFMifare_LoadKey(4, 13, ymima(0))
If status <> 0 Then
StatusBar1.Panels(3).Text = " 密码传送失败！"
Exit Sub
End If

status = RFMifare_Authentication(4, 13, 55)
If status <> 0 Then
StatusBar1.Panels(3).Text = " 密码校验失败！"
Exit Sub
End If

status = RFMifare_Read(52, ReadBuff(0))
......

[haj77]

of123() ，看了你的Mifare卡调用函数，在RFMifare_Read(52, ReadBuff(0))中，你ReadBuff
定义长度为0, 使用函数后可以看到返回数据吗？ 我可以用Email与你交流吗？

[haj77]

并且现在有个怪问题，在使用Mifare_Read函数时，如果将buffer定义成byref buffer as byte
类型时，运行函数报xxxxx地址不能为"read"错误？

[of123]

RFMifare_Read(52, ReadBuff(0))中ReadBuff(0)是地址指针，指向下标为零的单元，即起始地址。
你事先要声明数组
Public ReadBuff(16) As Byte