[C#]Enable UAC Shield icons and run as administrator
在Win7中常會看到某些程式中會有個按鈕，按鈕上會有個盾牌的圖示，按下後能提升存取權限。這邊紀錄一下這樣的功能要怎樣實現。
首先是盾牌的圖示，實作時不是自己去換按鈕的圖片，而是要對Button發送BCM_SETSHIELD(0x0000160C)的Message，訊息發送時lParam參數帶1或0去決定是否顯示盾牌圖示。這邊需注意的是因為這功能在vista以前不提供，所以必須做些處理，另外則是這功能必須要將按鈕的FlatStyle設為System，運行後才會有效果。
#region Const
const int BCM_SETSHIELD = 0x0000160C;
#endregion
#region Private Method
private static bool AtLeastVista()
{
return (Environment.OSVersion.Platform == PlatformID.Win32NT && Environment.OSVersion.Version.Major >= 6);
}
private static void SetButtonShield(Button btn, bool showShield)
{
if (!AtLeastVista())
return;
btn.FlatStyle = FlatStyle.System;
SendMessage(new HandleRef(btn, btn.Handle), BCM_SETSHIELD, IntPtr.Zero, showShield ? new IntPtr(1) : IntPtr.Zero);
}
#endregion
提升權限的部分則是透過Process去實現RunAs功能，比較要注意的是要帶入當下執行檔的位置，並將Verb設為runas。
ProcessStartInfo psi = new ProcessStartInfo
{
Arguments = "-justelevated",
ErrorDialog = true,
ErrorDialogParentHandle = form.Handle,
FileName = Application.ExecutablePath,
Verb = "runas"
};
這邊筆者方便後續使用，將其整理為擴充方法。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Diagnostics;
public static class ButtonExtension
{
#region DllImport
[DllImport("shell32.dll", EntryPoint = "#680", CharSet = CharSet.Unicode)]
private static extern bool IsUserAnAdmin();
[DllImport("user32.dll", CharSet = CharSet.Unicode)]
private static extern IntPtr SendMessage(HandleRef hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
#endregion
#region Const
const int BCM_SETSHIELD = 0x0000160C;
#endregion
#region Private Method
private static bool AtLeastVista()
{
return (Environment.OSVersion.Platform == PlatformID.Win32NT && Environment.OSVersion.Version.Major >= 6);
}
private static void SetButtonShield(Button btn, bool showShield)
{
if (!AtLeastVista())
return;
btn.FlatStyle = FlatStyle.System;
SendMessage(new HandleRef(btn, btn.Handle), BCM_SETSHIELD, IntPtr.Zero, showShield ? new IntPtr(1) : IntPtr.Zero);
}
private static Form GetWindowForm(Control control)
{
Control parent = control.Parent;
if (parent == null)
return null;
if(parent is Form)
return parent as Form;
return GetWindowForm(parent);
}
#endregion
#region Public Method
public static void EnableShieldIcon(this Button button)
{
SetButtonShield(button, true);
}
public static void EnableRunAsProcess(this Button button)
{
button.Click -= new EventHandler(button_RunAsProcess);
button.Click += new EventHandler(button_RunAsProcess);
}
#endregion
#region Event Process
private static void button_RunAsProcess(object sender, EventArgs e)
{
Button button = sender as Button;
Form form = GetWindowForm(button);
if (form == null)
return;
ProcessStartInfo psi = new ProcessStartInfo
{
Arguments = "-justelevated",
ErrorDialog = true,
ErrorDialogParentHandle = form.Handle,
FileName = Application.ExecutablePath,
Verb = "runas"
};
try
{
Process.Start(psi);
form.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
#endregion
}
使用時對Button去設定EnableShieldIcon與EnableRunAsProcess就可以了。
private void Form1_Load(object sender, EventArgs e)
{
button1.EnableShieldIcon();
button1.EnableRunAsProcess();
}
運行後就會看到盾牌圖示，點擊按鈕也會將權限提升。
