主题：调取存储在扫码枪里的数据（厂家有提供dll）

类似参考 http://www.foxtable.com/webhelp/scr/2417.htm

 

1、拷贝dll到安装目录；

 

2、在全局代码声明函数

 

Public Declare Function Read_data Lib "get_API.dll" Alias "Read_data" (addr As ulong, len As uinteger, byref data As Stringbuilder) As Char

 

3、调用

 

Dim addr = &H2000
Dim len = 60
Dim data As new Stringbuilder(60)
Dim result = Read_data(Addr,len,data)
msgbox(result)
msgbox(data.Tostring)

闪退有可能是foxtable不能使用你这个dll文件。

 

你用vs新建一个vb.net的项目，然后测试3楼代码。

1、把dll文件拷贝到项目的debug文件夹。

 

2、加一个按钮，写这个代码

 

Dim addr = &H2000
Dim len = 60
Dim data As new Stringbuilder(60)
Dim result = Read_data(Addr,len,data)
msgbox(result)
msgbox(data.Tostring)

 

 

3、定义的代码，写到按钮代码的外面去。

Imports System.Text

Public Class Form1
    Public Declare Function Read_data Lib "get_API.dll" Alias "Read_data" (addr As ULong, len As UInteger, ByRef data As StringBuilder) As Char

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim addr = &H2000
        Dim len = 60
        Dim data As New StringBuilder(60)
        Dim result = Read_data(addr, len, data)
        MsgBox(result)
        MsgBox(data.ToString)

    End Sub
End Class

新建的vb.net项目，平台请改成 .net framework 2.0 （右键属性那里设置）

如果你不插入设备，直接执行代码，也报错？

 

我执行执行没问题。我的是32位的操作系统，如果你的事64位的，你可能需要更换成64为的dll文件。

 

试试改成，如果不行，那你叫厂家给你一个C#或者vb.net的实例

 

Imports System.Text

Public Class Form1
    Public Declare Function Read_data Lib "get_API.dll" Alias "Read_data" (addr As ULong, len As Byte, ByRef data As Byte()) As Byte

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim addr As ULong = &H2000
        Dim len As Byte = 60
        Dim data(60) As Byte
        Dim result = Read_data(addr, len, data)
        MsgBox(result)
        MsgBox(data.length) 

    End Sub
End Class

 

------------------------------------------------

 

 

Imports System.Text

Public Class Form1
    Public Declare Function Read_data Lib "get_API.dll" Alias "Read_data" (addr As ULong, len As Byte, ByRef data As StringBuilder) As Byte

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim addr As ULong = &H2000
        Dim len As Byte = 60
        Dim data as new stringbuilder(60)
        Dim result = Read_data(addr, len, data)
        MsgBox(result)
        MsgBox(data.tostring) 

 

    End Sub
End Class

1、是不是你的设置码错了？

 

果不行，那你叫厂家给你一个C#或者vb.net的实例。关键是那个函数要怎么声明使用。