VB调用Delphi编写的DLL - 2

本篇讲程序2！

本程序主要有两个功能：计算CRC32数值和读取FCN文件的内容。

通过这个两个数值的对比可以发现是否文件被修改过！

1. 按钮事件cmdCal_Click()

Label_cal.Caption = calCRC32(filePath1)

此接口有1个参数：

'定义要计算的文件(具体路径和文件名称)
Dim filePath1 As String

外调函数声明：

'vb define
Option Explicit
Private Declare Function calCRC32 Lib "FCN.dll" (ByVal filePath1 As String) As Long

2. 按钮事件cmdReadFCN_Click()

Label_read.Caption = readFCN(loadFile1)

此接口有1个参数：

'定义要读取的文件(具体路径和文件名称)
Dim loadFile1 As String

外调函数声明：

Private Declare Function readFCN Lib "FCN.dll" (ByVal loadFile1 As String) As Long

下面是完整的代码（frmDemCrc32.frm）：

VERSION 5.00
Begin VB.Form frmDemCrc32
Caption         =   "CRC32演示"
ClientHeight    =   2790
ClientLeft      =   60
ClientTop       =   345
ClientWidth     =   8895
BeginProperty Font
Name            =   "宋体"
Size            =   9.75
Charset         =   134
Weight          =   400
Underline       =   0   'False
Italic          =   0   'False
Strikethrough   =   0   'False
EndProperty
LinkTopic       =   "Form1"
ScaleHeight     =   2790
ScaleWidth      =   8895
StartUpPosition =   2  'CenterScreen
Begin VB.TextBox fcnPathTxt
Height          =   495
Left            =   600
TabIndex        =   7
Text            =   "c:\s\datasb.fcn"
Top             =   1320
Width           =   3735
End
Begin VB.TextBox filePathTxt
Height          =   495
Left            =   600
TabIndex        =   6
Text            =   "c:\s\datasb.txt"
Top             =   360
Width           =   3735
End
Begin VB.CommandButton cmdReadFCN
Caption         =   "读 FCN 文件"
BeginProperty Font
Name            =   "宋体"
Size            =   9
Charset         =   134
Weight          =   400
Underline       =   0   'False
Italic          =   0   'False
Strikethrough   =   0   'False
EndProperty
Height          =   495
Left            =   7440
TabIndex        =   1
Top             =   1320
Width           =   1215
End
Begin VB.CommandButton cmdCal
Caption         =   "计算CRC32值"
BeginProperty Font
Name            =   "宋体"
Size            =   9
Charset         =   134
Weight          =   400
Underline       =   0   'False
Italic          =   0   'False
Strikethrough   =   0   'False
EndProperty
Height          =   495
Left            =   7440
TabIndex        =   0
Top             =   360
Width           =   1215
End
Begin VB.Label Label2
Caption         =   "读取值："
BeginProperty Font
Name            =   "宋体"
Size            =   9
Charset         =   134
Weight          =   400
Underline       =   0   'False
Italic          =   0   'False
Strikethrough   =   0   'False
EndProperty
Height          =   495
Left            =   4560
TabIndex        =   5
Top             =   1440
Width           =   735
End
Begin VB.Label Label1
Caption         =   "计算值："
BeginProperty Font
Name            =   "宋体"
Size            =   9
Charset         =   134
Weight          =   400
Underline       =   0   'False
Italic          =   0   'False
Strikethrough   =   0   'False
EndProperty
Height          =   495
Left            =   4560
TabIndex        =   4
Top             =   480
Width           =   735
End
Begin VB.Label Label_read
ForeColor       =   &H80000001&
Height          =   495
Left            =   5640
TabIndex        =   3
Top             =   1440
Width           =   1605
End
Begin VB.Label Label_cal
ForeColor       =   &H80000001&
Height          =   495
Left            =   5640
TabIndex        =   2
Top             =   480
Width           =   1605
End
End
Attribute VB_Name = "frmDemCrc32"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Private Declare Function calCRC32 Lib "FCN.dll" (ByVal filePath1 As String) As Long

Private Declare Function readFCN Lib "FCN.dll" (ByVal loadFile1 As String) As Long

Private Sub cmdCal_Click()
'定义要计算的文件(具体路径和文件名称)
Dim filePath1 As String
filePath1 = filePathTxt.Text

'调用函数
Label_cal.Caption = calCRC32(filePath1)

End Sub

Private Sub cmdReadFCN_Click()
'定义要读取的文件(具体路径和文件名称)
Dim loadFile1 As String
loadFile1 = fcnPathTxt.Text

'调用函数
Label_read.Caption = readFCN(loadFile1)
End Sub

附：

说明文件

文件接口
—CRC32动态库（FCN.DLL）

一、函数列表

函数名称	参数名称	数据类型	返回值	备注
calCRC32	filePath1	String	Long	计算文件的CRC32值
readFCN	loadFile1	String	Long	读取FCN文件的CRC32值

二、VB声明

1． 计算文件的CRC32值

‘VB声明

PrivateDeclare Function calCRC32 Lib "FCN.dll" (ByVal filePath1 As String)As Long

2． 读取FCN文件的CRC32值

‘VB声明

Private Declare Function readFCN Lib"FCN.dll" (ByVal loadFile1 As String) As Long

使用说明：（xiaobin）

请把MSVBVM60.DLL和FCN.dll与程序文件在一个目录里！

下载地址：http://download.csdn.net/detail/binbsu37/4304645