如何使用Windows 服务设置桌面背景图片

Question

用C# 写了个服务，在服务中调用 SystemParametersInfo(20,0,"图片路径",1) 函数，总是返回失败，操作系统是win10,但是通过普通的Winform 程序调用此函数却是OK,求教这是什么原因呢？

Answer 1

每个用户的 桌面背景图片 是不同的吧。 windows service默认不是运行在当前登录用户下的。

你试一试在Service的属性的log on页中，用的你的当前登录用户运行一下service试一试是不是能调用成功。

Answer 2

看是不是服务里面

Allow service to inerract with desktop

这个没有勾上

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专注于.NET MIS开发框架，C/S架构，SQL Server + ORM(LLBL Gen Pro) + Infragistics WinForms

Answer 3

谢谢，问题已经解决了，不过除了这一项之外还用到了一个第三方的动态库 Cjwdev.WindowsApi.dll

通过下面的代码，设置服务安装完之后，勾选允许服务于桌面交互

 private void serviceInstaller1_AfterInstall(object sender, InstallEventArgs e)
        {
            //允许服务和用户界面交互
            ConnectionOptions coOptions = new ConnectionOptions();
            coOptions.Impersonation = ImpersonationLevel.Impersonate;
            ManagementScope mgmtScope = new System.Management.ManagementScope(@"root\CIMV2", coOptions);
            mgmtScope.Connect();
            ManagementObject wmiService;
            wmiService = new ManagementObject("Win32_Service.Name='" + this.serviceInstaller1.ServiceName + "'");
            ManagementBaseObject InParam = wmiService.GetMethodParameters("Change");
            InParam["DesktopInteract"] = true;
            ManagementBaseObject OutParam = wmiService.InvokeMethod("Change", InParam, null);
        }

Answer 4

谢谢提醒，现在问题已经解决，解决的方式是

1、允许服务与桌面应用交互

2、引用的第三方的DLL(Cjwdev.WindowsApi)

主要代码如下:

1、允许服务与桌面应用交互

 private void serviceInstaller1_AfterInstall(object sender, InstallEventArgs e)
        {
            //允许服务和用户界面交互
            ConnectionOptions coOptions = new ConnectionOptions();
            coOptions.Impersonation = ImpersonationLevel.Impersonate;
            ManagementScope mgmtScope = new System.Management.ManagementScope(@"root\CIMV2", coOptions);
            mgmtScope.Connect();
            ManagementObject wmiService;
            wmiService = new ManagementObject("Win32_Service.Name='" + this.serviceInstaller1.ServiceName + "'");
            ManagementBaseObject InParam = wmiService.GetMethodParameters("Change");
            InParam["DesktopInteract"] = true;
            ManagementBaseObject OutParam = wmiService.InvokeMethod("Change", InParam, null);
        }

2、引用第三方动态库(Cjwdev.WindowsApi.dll),在服务启动后调用我的应用程序，更改桌面代码的逻辑放置在我的应用程序中。

  protected override void OnStart(string[] args)
        {

            //我的应用程序路径
            string appStartPath = @"C:\\SV\\ChangeImageWinFormUI.exe";
            IntPtr userTokenHandle = IntPtr.Zero;
            ApiDefinitions.WTSQueryUserToken(ApiDefinitions.WTSGetActiveConsoleSessionId(), ref userTokenHandle);
            ApiDefinitions.PROCESS_INFORMATION procInfo = new ApiDefinitions.PROCESS_INFORMATION();
            ApiDefinitions.STARTUPINFO startInfo = new ApiDefinitions.STARTUPINFO();
            startInfo.cb = (uint)Marshal.SizeOf(startInfo);
            ApiDefinitions.CreateProcessAsUser(userTokenHandle, appStartPath, "", IntPtr.Zero, IntPtr.Zero, false, 0, IntPtr.Zero, null, ref startInfo, out procInfo);
            if (userTokenHandle != IntPtr.Zero)
                ApiDefinitions.CloseHandle(userTokenHandle);
            int _currentAquariusProcessId = (int)procInfo.dwProcessId;

        }