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