警告:包含大量代码的长帖子。
当您将 Web 浏览器控件导航到文件系统文件夹时,Web 浏览器控件会承载一个 shell 视图窗口,该窗口又承载资源管理器列表视图。事实上,这与 Explorer 进程以及文件对话框和 Internet Explorer 所做的完全相同。这个 shell 窗口不是一个控件,因此没有可以在其上调用的方法或可以订阅的事件,但它可以接收窗口消息并且可以被子类化。
事实证明,处理自动将视图设置为 Details 的问题部分实际上非常简单。在 Web 浏览器控件的 Navigated 事件中,只需找到 shell 视图窗口的句柄并向其发送带有特定 shell 常量 (SHVIEW_REPORT) 的 WM_COMMAND 消息。这是一个未记录的命令,但它在包括 Windows 2008 在内的所有 Windows 平台上都受支持,并且几乎可以肯定会在 Windows 7 上。添加到 Web 浏览器表单的一些代码证明了这一点:
private delegate int EnumChildProc(IntPtr hwnd, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true)]
private static extern IntPtr SendMessage(IntPtr hWnd, int Msg,
IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true)]
private static extern int EnumChildWindows(IntPtr hWndParent,
EnumChildProc lpEnumFunc, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
private static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName,
int nMaxCount);
private const int WM_COMMAND = 0x0111;
private const int SHVIEW_REPORT = 0x702C;
private const string SHELLVIEW_CLASS = "SHELLDLL_DefView";
private IntPtr m_ShellView;
void webBrowser1_Navigated(object sender, WebBrowserNavigatedEventArgs e)
{
m_ShellView = IntPtr.Zero;
EnumChildWindows(webBrowser1.Handle, EnumChildren, IntPtr.Zero);
if (m_ShellView != IntPtr.Zero)
{
SendMessage(m_ShellView, WM_COMMAND, (IntPtr)SHVIEW_REPORT, (IntPtr)0);
}
}
private int EnumChildren(IntPtr hwnd, IntPtr lParam)
{
int retval = 1;
StringBuilder sb = new StringBuilder(SHELLVIEW_CLASS.Length + 1);
int numChars = GetClassName(hwnd, sb, sb.Capacity);
if (numChars == SHELLVIEW_CLASS.Length)
{
if (sb.ToString(0, numChars) == SHELLVIEW_CLASS)
{
m_ShellView = hwnd;
retval = 0;
}
}
return retval;
}
每次 Web 浏览器导航到新窗口时(包括从资源管理器视图中打开文件夹时),都会创建一个新的 shell 视图窗口,因此必须在每个 Navigated 事件中将消息重新发送到新窗口。
对于您问题的第二部分,您希望从资源管理器列表视图中接收事件。这比第一部分要困难得多。为此,您需要对列表视图窗口进行子类化,然后监视您感兴趣的窗口消息(例如 WM_LBUTTONDBLCLK)。为了对窗口进行子类化,您需要创建自己的从 NativeWindow 类派生的类,并为其分配您需要监视的窗口的句柄。然后,您可以覆盖其 Window 过程并根据需要处理各种消息。下面是一个创建双击事件的示例 - 它相对简单,但要广泛访问资源管理器列表视图可能需要比您愿意做的更多工作。
将此添加到您的表单中:
private ExplorerListView m_Explorer;
void OnExplorerItemExecuted(object sender, ExecuteEventArgs e)
{
string msg = string.Format("Item to be executed: {0}{0}{1}",
Environment.NewLine, e.SelectedItem);
e.Cancel = (MessageBox.Show(msg, "", MessageBoxButtons.OKCancel)
== DialogResult.Cancel);
}
这两行到 Navigated 事件处理程序(就在 SendMessage 之后):
m_Explorer = new ExplorerListView(m_ShellView);
m_Explorer.ItemExecuted += OnExplorerItemExecuted;
然后添加以下类:
class ExplorerListView : NativeWindow
{
public event EventHandler<ExecuteEventArgs> ItemExecuted;
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
private static extern IntPtr SendMessage(IntPtr hWnd, int Msg,
IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
private static extern IntPtr FindWindowEx(IntPtr hwndParent,
IntPtr hwndChildAfter, string lpszClass, string lpszWindow);
private const int WM_LBUTTONDBLCLK = 0x0203;
private const int LVM_GETNEXTITEM = 0x100C;
private const int LVM_GETITEMTEXT = 0x1073;
private const int LVNI_SELECTED = 0x0002;
private const string EXPLORER_LISTVIEW_CLASS = "SysListView32";
public ExplorerListView(IntPtr shellViewHandle)
{
base.AssignHandle(FindWindowEx(shellViewHandle, IntPtr.Zero,
EXPLORER_LISTVIEW_CLASS, null));
if (base.Handle == IntPtr.Zero)
{
throw new ArgumentException("Window supplied does not encapsulate an explorer window.");
}
}
protected override void WndProc(ref Message m)
{
switch (m.Msg)
{
case WM_LBUTTONDBLCLK:
if (OnItemExecution() != 0) return;
break;
default:
break;
}
base.WndProc(ref m);
}
private int OnItemExecution()
{
int cancel = 0;
ExecuteEventArgs args = new ExecuteEventArgs(GetSelectedItem());
EventHandler<ExecuteEventArgs> temp = ItemExecuted;
if (temp != null)
{
temp(this, args);
if (args.Cancel) cancel = 1;
}
return cancel;
}
private string GetSelectedItem()
{
string item = null;
IntPtr pStringBuffer = Marshal.AllocHGlobal(2048);
IntPtr pItemBuffer = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(LVITEM)));
int selectedItemIndex = SendMessage(base.Handle, LVM_GETNEXTITEM, (IntPtr)(-1), (IntPtr)LVNI_SELECTED).ToInt32();
if (selectedItemIndex > -1)
{
LVITEM lvi = new LVITEM();
lvi.cchTextMax = 1024;
lvi.pszText = pStringBuffer;
Marshal.StructureToPtr(lvi, pItemBuffer, false);
int numChars = SendMessage(base.Handle, LVM_GETITEMTEXT, (IntPtr)selectedItemIndex, pItemBuffer).ToInt32();
if (numChars > 0)
{
item = Marshal.PtrToStringUni(lvi.pszText, numChars);
}
}
Marshal.FreeHGlobal(pStringBuffer);
Marshal.FreeHGlobal(pItemBuffer);
return item;
}
struct LVITEM
{
public int mask;
public int iItem;
public int iSubItem;
public int state;
public int stateMask;
public IntPtr pszText;
public int cchTextMax;
public int iImage;
public IntPtr lParam;
public int iIndent;
public int iGroupId;
int cColumns; // tile view columns
public IntPtr puColumns;
public IntPtr piColFmt;
public int iGroup;
}
}
public class ExecuteEventArgs : EventArgs
{
public string SelectedItem { get; private set; }
public bool Cancel { get; set; }
internal ExecuteEventArgs(string selectedItem)
{
SelectedItem = selectedItem;
}
}
这应该让你知道你需要做什么。如果您想要的不仅仅是相当简单的事件,您可能需要寻找替代控件,尽管从我在免费和低成本区域中看到的情况来看,有一些相当不错的控件,但它们都有一些怪癖并且不会提供无缝的资源管理器经验。
请记住,此代码很快就组合在一起,没有错误处理或注释,并且忽略了多个问题,例如多个选定的项目,因此将其用作指南,风险自负。