C#窗体全屏功能实例代码

最近有朋友让我给他弄个应用程序全屏的功能，例如银行的取号程序界面。所以我从网上查询了一些实现的方法。

c#应用程序中如何实现全屏幕显示功能？
效果就像windows自带的屏幕保护程序和众多的游戏那样，无论是否设置了“将任务栏保持在其他窗口的前端”都不显示任务栏

实现方式一

在网上找来一些简单的实现方式：

this.formborderstyle = formborderstyle.none;  //设置窗体为无边框样式
this.windowstate = formwindowstate.maximized; //最大化窗体 

然后再设置窗体的位置和大小，例如：width=1024 height=768 left=0 top=0等size的值

把以上两句代码直接放到form1_load的方法中，就可以了，比较简单，我就不贴代码了。

实现方式二

调用系统的api函数，如user32.dll中的findwindow和showwindow函数，具体代码如下：

 [dllimport("user32.dll", entrypoint = "showwindow")]
  public static extern int32 showwindow(int32 hwnd, int32 ncmdshow);

  [dllimport("user32.dll", entrypoint = "findwindow")]
  private static extern int32 findwindow(string lpclassname, string lpwindowname);

代码如下：

using system;
using system.windows.forms;

using system.drawing;
using system.runtime.interopservices;


namespace fullscr
{
 public partial class form1 : form
 {

  boolean m_isfullscreen = false;//标记是否全屏


  public form1()
  {
   initializecomponent();
  }


  private void form1_load(object sender, eventargs e)
  {
  }

  /// <summary>
  /// 全屏按钮的click事件
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void button1_click(object sender, eventargs e)
  {
   m_isfullscreen = !m_isfullscreen;//点一次全屏，再点还原。 
   this.suspendlayout();
   if (m_isfullscreen)//全屏 ,按特定的顺序执行
   {
    setformfullscreen(m_isfullscreen);
    this.formborderstyle = formborderstyle.none;
    this.windowstate = formwindowstate.maximized;
    this.activate();//
   }
   else//还原，按特定的顺序执行——窗体状态，窗体边框，设置任务栏和工作区域
   {
    this.windowstate = formwindowstate.normal;
    this.formborderstyle = formborderstyle.sizable;
    setformfullscreen(m_isfullscreen);
    this.activate();
   }
   this.resumelayout(false);
  }

  /// <summary> 
  /// 设置全屏或这取消全屏 
  /// </summary> 
  /// <param name="fullscreen">true:全屏 false:恢复</param> 
  /// <param name="rectold">设置的时候，此参数返回原始尺寸，恢复时用此参数设置恢复</param> 
  /// <returns>设置结果</returns> 
  public boolean setformfullscreen(boolean fullscreen)//, ref rectangle rectold
  {
   rectangle rectold = rectangle.empty;
   int32 hwnd = 0;
   hwnd = findwindow("shell_traywnd", null);//获取任务栏的句柄

   if (hwnd == 0) return false;

   if (fullscreen)//全屏
   {
    showwindow(hwnd, sw_hide);//隐藏任务栏

    systemparametersinfo(spi_getworkarea, 0, ref rectold, spif_updateinifile);//get屏幕范围
    rectangle rectfull = screen.primaryscreen.bounds;//全屏范围
    systemparametersinfo(spi_setworkarea, 0, ref rectfull, spif_updateinifile);//窗体全屏幕显示
   }
   else//还原 
   {
    showwindow(hwnd, sw_show);//显示任务栏
    systemparametersinfo(spi_setworkarea, 0, ref rectold, spif_updateinifile);//窗体还原
   }
   return true;
  }

  #region user32.dll

  public const int32 spif_updateinifile = 0x1;
  public const int32 spi_setworkarea = 47;
  public const int32 spi_getworkarea = 48;
  public const int32 sw_show = 5;
  public const int32 sw_hide = 0;

  [dllimport("user32.dll", entrypoint = "showwindow")]
  public static extern int32 showwindow(int32 hwnd, int32 ncmdshow);

  [dllimport("user32.dll", entrypoint = "findwindow")]
  private static extern int32 findwindow(string lpclassname, string lpwindowname);

  [dllimport("user32.dll", entrypoint = "systemparametersinfo")]
  private static extern int32 systemparametersinfo(int32 uaction, int32 uparam, ref rectangle lpvparam, int32 fuwinini);

  #endregion

 }
}

完善后的代码：

非常感谢@iheartwater的热心帮助，更改后的代码能够解决”全屏后，窗体能够恢复到原来的状态，包括位置（loaction）和大小（size）“，唉，其实，原因还挺简单的。

modified code
 public partial class frmfullscreen : form
 {
  boolean m_isfullscreen = false;//标记是否全屏

  public frmfullscreen()
  {
   initializecomponent();
  }
  /// <summary>
  /// 全屏按钮的click事件
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void btnfullscreen_click(object sender, eventargs e)
  {
   m_isfullscreen = !m_isfullscreen;//点一次全屏，再点还原。 
   this.suspendlayout();
   if (m_isfullscreen)//全屏 ,按特定的顺序执行
   {
    setformfullscreen(m_isfullscreen);
    this.formborderstyle = formborderstyle.none;
    this.windowstate = formwindowstate.maximized;
    this.activate();//
   }
   else//还原，按特定的顺序执行——窗体状态，窗体边框，设置任务栏和工作区域
   {
    this.windowstate = formwindowstate.normal;
    this.formborderstyle = formborderstyle.sizable;
    setformfullscreen(m_isfullscreen);
    this.activate();
   }
   this.resumelayout(false);
  }
  /// <summary>
  /// 全屏的快捷功能，f11相当于单机按钮；esc健，如果全屏则退出全屏
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void btnfullscreen_keydown(object sender, keyeventargs e)
  {
   if (e.keycode == keys.f11)
   {
    btnfullscreen.performclick();
    e.handled = true;
   }
   else if (e.keycode == keys.escape)//esc键盘退出全屏
   {
    if (m_isfullscreen)
    {
     e.handled = true;
     this.windowstate = formwindowstate.normal;//还原 
     this.formborderstyle = formborderstyle.sizable;
     setformfullscreen(false);
    }
   }
  }
  /// <summary> 
  /// 设置全屏或这取消全屏 
  /// </summary> 
  /// <param name="fullscreen">true:全屏 false:恢复</param> 
  /// <param name="rectold">设置的时候，此参数返回原始尺寸，恢复时用此参数设置恢复</param> 
  /// <returns>设置结果</returns> 
  public boolean setformfullscreen(boolean fullscreen)//, ref rectangle rectold
  {
   rectangle rectold=rectangle.empty;
   int32 hwnd = 0;
   hwnd = findwindow("shell_traywnd", null);//获取任务栏的句柄

   if (hwnd == 0) return false;

   if (fullscreen)//全屏
   {
    showwindow(hwnd, sw_hide);//隐藏任务栏

    systemparametersinfo(spi_getworkarea, 0, ref rectold, spif_updateinifile);//get 屏幕范围
    rectangle rectfull = screen.primaryscreen.bounds;//全屏范围
    systemparametersinfo(spi_setworkarea, 0, ref rectfull, spif_updateinifile);//窗体全屏幕显示
   }
   else//还原 
   {
    showwindow(hwnd, sw_show);//显示任务栏

    systemparametersinfo(spi_setworkarea, 0, ref rectold, spif_updateinifile);//窗体还原
   }
   return true;
  }

  #region user32.dll

  [dllimport("user32.dll", entrypoint = "showwindow")]
  public static extern int32 showwindow(int32 hwnd, int32 ncmdshow);
  public const int32 sw_show = 5; public const int32 sw_hide = 0;

  [dllimport("user32.dll", entrypoint = "systemparametersinfo")]
  private static extern int32 systemparametersinfo(int32 uaction, int32 uparam, ref rectangle lpvparam, int32 fuwinini);
  public const int32 spif_updateinifile = 0x1;
  public const int32 spi_setworkarea = 47;
  public const int32 spi_getworkarea = 48;

  [dllimport("user32.dll", entrypoint = "findwindow")]
  private static extern int32 findwindow(string lpclassname, string lpwindowname);

  #endregion
 }

窗体全屏

窗体全屏的方法：

隐藏任务栏、设置工作区域
窗体最大化、设置窗体边框样式