我如何把我的WPF应用程序带到桌面的前面?到目前为止，我尝试过:
SwitchToThisWindow(new WindowInteropHelper(Application.Current.MainWindow).Handle, true);
SetWindowPos(new WindowInteropHelper(Application.Current.MainWindow).Handle, IntPtr.Zero, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
SetForegroundWindow(new WindowInteropHelper(Application.Current.MainWindow).Handle);
其中没有一个在做这项工作(Marshal.GetLastWin32Error()表示这些操作成功完成，并且每个定义的P/Invoke属性都具有SetLastError=true)。
如果我创建一个新的空白WPF应用程序，并使用计时器调用SwitchToThisWindow，它完全按照预期工作，所以我不确定为什么它在我原来的情况下不工作。
编辑:我这样做与一个全局热键。
既然这是个热门话题…以下是对我有效的方法。如果我不这样做，我就会得到错误，因为如果你看不到窗口，Activate()就会出错。
Xaml:
<Window ....
Topmost="True"
....
ContentRendered="mainWindow_ContentRendered"> .... </Window>
后台代码:
private void mainWindow_ContentRendered(object sender, EventArgs e)
{
this.Topmost = false;
this.Activate();
_UsernameTextBox.Focus();
}
这是唯一能让窗口在顶部显示的方法。然后激活它，这样你就可以在框中输入，而不必用鼠标设置焦点。control.Focus()不会工作，除非窗口是Active();
如果用户正在与另一个应用程序交互，则可能无法将您的应用程序放在前面。作为一般规则，只有当进程已经是前台进程时，该进程才能期望设置前台窗口。(微软在SetForegroundWindow() MSDN条目中记录了限制。)这是因为:
The user "owns" the foreground. For example, it would be extremely annoying if another program stole the foreground while the user is typing, at the very least interrupting her workflow, and possibly causing unintended consequences as her keystrokes meant for one application are misinterpreted by the offender until she notices the change.
Imagine that each of two programs checks to see if its window is the foreground and attempts to set it to the foreground if it is not. As soon as the second program is running, the computer is rendered useless as the foreground bounces between the two at every task switch.
让这个快速复制粘贴-
使用这个类的DoOnProcess方法将进程的主窗口移动到前台(但不是从其他窗口窃取焦点)
public class MoveToForeground
{
[DllImportAttribute("User32.dll")]
private static extern int FindWindow(String ClassName, String WindowName);
const int SWP_NOMOVE = 0x0002;
const int SWP_NOSIZE = 0x0001;
const int SWP_SHOWWINDOW = 0x0040;
const int SWP_NOACTIVATE = 0x0010;
[DllImport("user32.dll", EntryPoint = "SetWindowPos")]
public static extern IntPtr SetWindowPos(IntPtr hWnd, int hWndInsertAfter, int x, int Y, int cx, int cy, int wFlags);
public static void DoOnProcess(string processName)
{
var allProcs = Process.GetProcessesByName(processName);
if (allProcs.Length > 0)
{
Process proc = allProcs[0];
int hWnd = FindWindow(null, proc.MainWindowTitle.ToString());
// Change behavior by settings the wFlags params. See http://msdn.microsoft.com/en-us/library/ms633545(VS.85).aspx
SetWindowPos(new IntPtr(hWnd), 0, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_SHOWWINDOW | SWP_NOACTIVATE);
}
}
}
HTH
