目录

一、代码背景

二、主要工具

三、函数解析

1、FindWindow&＃xff1a;

2、 FindWindowEx&＃xff1a;

3、SendMessage&＃xff1a;

四、具体代码示例&＃xff1a;

 1、第一部分功能&＃xff1a;

A、接收端&＃xff1a;

B、发送端

C、运行测试

2.第二部分功能&＃xff1a;

A、接收端

B、发送端

C、运行测试

一、代码背景

 针对复杂的多进程软件的编写&＃xff0c;各进程间的通信能够保证任务的并行处理&＃xff0c;而非多线程的伪并行。针对VB.net进程通信&＃xff0c;本文所采用的是调用USER32内的Windows API函数。

二、主要工具

主要包括FindWindow、Fin的WindowEX、SendMessage函数。主要用到的工具为Visual Studio 和SPY&＃43;&＃43;&＃xff0c;SPY&＃43;&＃43;自行百度下载。

三、函数解析

1、FindWindow&＃xff1a;

根据标题名和窗体类别查找父窗体&＃xff0c;并返回窗体的句柄数。声明过程如下&＃xff1a;

    Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer

lpClassName&＃xff1a;窗体类的名字&＃xff0c;具体窗体类的名字可以通过SPY&＃43;&＃43;查看&＃xff1b;

lpWindowName&＃xff1a;窗体标题名字&＃xff0c;具体窗体标题名字可以通过SPY&＃43;&＃43;查看。

2、 FindWindowEx&＃xff1a;

根据父窗体的句柄&＃xff0c;和上一个子窗体的句柄及待查找的子窗体类名和窗体标题名字来查找待查找窗体的句柄。声明过程如下&＃xff1a;

Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As Integer

hWnd1&＃xff1a;父窗体句柄&＃xff1b;

hWnd2&＃xff1a;子窗体索引序号&＃xff0c;为0则根据Z序列检索左下角满足要求的窗体&＃xff0c;将得到的左下角窗体句柄赋给此参数&＃xff0c;则根据Z序列检索左下角窗体下一个窗体的句柄。

关于Z序列的解释&＃xff1a;子窗体在VB Form中的排序按照Z序列排序&＃xff0c;所谓Z序列是指在XY坐标系的第一象限根据Z的笔顺来排序的&＃xff0c;而由于电脑窗体的XY的方向是水平向右为X&＃xff0c;竖直向下为Y&＃xff0c;故与现实生活中的XY坐标系沿着X轴进行镜像&＃xff0c;如下图所示。

 依次检索上图右侧①②③④即可索引到对应位置窗体的句柄。

lpsz1&＃xff1a;子窗体类的名字&＃xff0c;具体窗体类的名字可以通过SPY&＃43;&＃43;查看&＃xff1b;

lpsz2&＃xff1a;子窗体标题的名字&＃xff0c;具体窗体标题的名字可以通过SPY&＃43;&＃43;查看&＃xff1b; 

关于lpsz2这个参数&＃xff0c;笔者尝试TextBox、RichTextBox、Label等控件的Text属性均未检索成功&＃xff0c;故采用VbNullString作为检索&＃xff0c;即不考虑窗体标题名字&＃xff0c;最终定位到每个句柄均依靠Z序列来实现。

3、SendMessage&＃xff1a;

根据提供的句柄和消息类型及其余两个参数来实现进程间的通信。声明如下&＃xff1a;

 Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Int32, ByVal wMsg As Int32, ByVal wParam As Int32, ByVal lParam As String) As Integer

hwnd&＃xff1a;窗体的句柄&＃xff1b;

wMsg&＃xff1a;消息类型&＃xff1b;

这个可以去看另一篇博主的文章&＃xff0c;讲解wMsg参数常量值的。本文引用几处。

wMsg参数常量值&＃xff1a;
　　#DeFine WM_CREATE 0x01
　　创建一个窗口
　　#DeFine WM_DESTROY 0x02
　　当一个窗口被破坏时发送
　　#DeFine WM_MOVE 0x03
　　移动一个窗口
　　#DeFine WM_SIZE 0x05
　　改变一个窗口的大小
　　#DeFine WM_ACTIVATE 0x06
　　一个窗口被激活或失去激活状态
　　#DeFine WM_SETFOCUS 0x07
　　一个窗口获得焦点
　　#DeFine WM_KILLFOCUS 0x08
　　一个窗口失去焦点
　　#DeFine WM_ENABLE 0x0A
　　一个窗口改变成Enable状态
　　#DeFine WM_SETREDRAW 0x0B
　　设置窗口是否能重画
　　#DeFine WM_SETTEXT 0x0C
　　应用程序发送此消息来设置一个窗口的文本
————————————————
版权声明&＃xff1a;本文为CSDN博主「物联网小镇」的原创文章&＃xff0c;遵循CC 4.0 BY-SA版权协议&＃xff0c;转载请附上原文出处链接及本声明。
原文链接&＃xff1a;https://blog.csdn.net/qq_41476542/article/details/106708127

其中　　#DeFine WM_SETTEXT 0x0C

是本文代码使用的常量&＃xff0c;十进制为12&＃xff0c;在VB.net中可以用十进制12表示&＃xff0c;或者&HC来表示16进制的12。表示的意思为发送此消息来设置一个窗口的文本。

wParam&＃xff1a;表示于常量有关的常量值&＃xff0c;这个参数笔者没搞懂&＃xff0c;但是默认0是好用的。

lParam&＃xff1a;发送的字符串信息。

四、具体代码示例&＃xff1a;

 1、第一部分功能&＃xff1a;

发送端检索接收端四个Textbox窗口的句柄信息&＃xff0c;并通过msgbox显示出来。

A、接收端&＃xff1a;

不用添加任何代码&＃xff0c;绘制四个Textbox&＃xff0c;修改窗体Text属性为Receive&＃xff0c;如下图所示。

运行接收端&＃xff0c;使用SPY&＃43;&＃43;查看TextBox文本框的类名 。

 B、发送端

绘制一个按钮 

 添加代码&＃xff1a;

Public Class Form1Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As IntegerPrivate Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As IntegerPrivate Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Int32, ByVal wMsg As Int32, ByVal wParam As Int32, ByVal lParam As String) As Int32Dim myhwnd As Integer &＃39;主窗口句柄Dim sub_1Hwnd As Integer &＃39;子窗口1句柄Dim sub_2Hwnd As Integer &＃39;子窗口2句柄Dim sub_3Hwnd As Integer &＃39;子窗口3句柄Dim sub_4Hwnd As Integer &＃39;子窗口4句柄Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Clickmyhwnd &＃61; FindWindow("WindowsForms10.Window.8.app.0.141b42a_r7_ad1", "Receive") ’检索主窗体句柄sub_1Hwnd &＃61; FindWindowEx(myhwnd, 0, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口1句柄sub_2Hwnd &＃61; FindWindowEx(myhwnd, sub_1Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口2句柄sub_3Hwnd &＃61; FindWindowEx(myhwnd, sub_2Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口3句柄sub_4Hwnd &＃61; FindWindowEx(myhwnd, sub_3Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口4句柄MsgBox(Hex(sub_1Hwnd) &＃43; " " &＃43; Hex(sub_2Hwnd) &＃43; " " &＃43; Hex(sub_3Hwnd) &＃43; " " &＃43; Hex(sub_4Hwnd)) ’以16进制字符串显示句柄信息End Sub
End Class

C、运行测试

先运行接收端&＃xff0c;再运行发送端并单击Button1测试&＃xff1a;

弹出对话框&＃xff0c;得出如下16进制句柄&＃xff1a;

210EE6、171014、210604、191022

再次使用SPY&＃43;&＃43;查找各个窗口的句柄

 满足我们推算的Z序列。

2.第二部分功能&＃xff1a;

验证SendMessage通信&＃xff0c;本代码Z序列中第2个窗口为例。

A、接收端

窗体控件不动&＃xff0c;添加代码

Public Class Form1Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.LoadTextBox3.Text &＃61; "窗口2"End SubPrivate Sub TextBox3_TextChanged(sender As Object, e As EventArgs) Handles TextBox3.TextChanged &＃39;Texebox3窗口内容改变If TextBox3.Text <> "窗口2" Then &＃39;Texebox3窗口内容不等于窗口2MsgBox("收到数据&＃xff1a;" &＃43; TextBox3.Text) &＃39;弹出收到数据&＃xff1a;对话框End IfTextBox3.Text &＃61; "窗口2" &＃39;恢复默认值窗口2End Sub
End Class

B、发送端

窗体增加Textbox控件作为发送信息的文本载体&＃xff0c;如图

代码修改如下,增加SendMessage函数的调用:

Public Class Form1Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As IntegerPrivate Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As IntegerPrivate Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Int32, ByVal wMsg As Int32, ByVal wParam As Int32, ByVal lParam As String) As Int32Dim myhwnd As Integer &＃39;主窗口句柄Dim sub_1Hwnd As Integer &＃39;子窗口1句柄Dim sub_2Hwnd As Integer &＃39;子窗口2句柄Dim sub_3Hwnd As Integer &＃39;子窗口3句柄Dim sub_4Hwnd As Integer &＃39;子窗口4句柄Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Clickmyhwnd &＃61; FindWindow("WindowsForms10.Window.8.app.0.141b42a_r7_ad1", "Receive") ’检索主窗体句柄sub_1Hwnd &＃61; FindWindowEx(myhwnd, 0, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口1句柄sub_2Hwnd &＃61; FindWindowEx(myhwnd, sub_1Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口2句柄sub_3Hwnd &＃61; FindWindowEx(myhwnd, sub_2Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口3句柄sub_4Hwnd &＃61; FindWindowEx(myhwnd, sub_3Hwnd, "WindowsForms10.EDIT.app.0.141b42a_r7_ad1", vbNullString) ’检索子窗口4句柄&＃39;MsgBox(Hex(sub_1Hwnd) &＃43; " " &＃43; Hex(sub_2Hwnd) &＃43; " " &＃43; Hex(sub_3Hwnd) &＃43; " " &＃43; Hex(sub_4Hwnd)) ’以16进制字符串显示句柄信息SendMessage(sub_2Hwnd, 12, 0, TextBox1.Text)TextBox1.Text &＃61; ""End Sub
End Class

C、运行测试

先运行接收端&＃xff0c;再运行发送端&＃xff0c;待发送窗口填写"Hello World"。并单击Button1&＃xff08;发送数据&＃xff09;测试&＃xff0c;如接收端弹出&＃xff1a;"接收数据&＃xff1a;Hello World"。则测试成功

运行结果如图

 笔者水平有限&＃xff0c;如有不足之处&＃xff0c;评论区欢迎指教。

源码如

https://download.csdn.net/download/qq835128030/21700002?spm&＃61;1001.2014.3001.5503

注&＃xff1a;Z序列理解有误&＃xff0c;经过实践&＃xff0c;笔者所推论的Z序列的理论属于巧合&＃xff0c;sub_1Hwnd、sub_2Hwnd、sub_3Hwnd、sub_4Hwnd的值无论接收窗口文本框如何排列&＃xff0c;均依次等于Textbox4、Textbox3、、Textbox2、、Textbox1的句柄。即文本框窗口的句柄检索排序按照放置的先后顺序的逆序&＃xff0c;先放后检索。后放先检索。作如上修订。2021/08/30 23:19