原文:FlashWindowEx实现窗口在任务栏闪烁/变化颜色
效果类似QQ收到新的会话消息任务栏颜色变化
附2小段代码：
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern int FlashWindow (int hwnd, int bInvert);
private void button1_Click(object sender, System.EventArgs e)
{
FlashWindow(this.Handle.ToInt32(),1); // 参数为1时启动闪烁, 参数为0时停止闪烁
}
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern bool FlashWindow(
IntPtr hWnd, // handle to window
bool bInvert // flash status
);
private void button1_Click(object sender, EventArgs e)
{ FlashWindow(this.Handle, true);
}当后台应用程序完成工作,可以通过闪动窗体来通知用户.
1.利用窗体的Activate方法
this.Activate();
此方法会直接将目标窗体显示在当前工作窗体的前面.并且当目标窗体被最小化时,使用此方法基本无效.
2.利用Windows API-FlashWindowEx
查了MSDN发现与Flash Window相关的API有两个:
一个FlashWindow,函数原型为:
BOOL WINAPI FlashWindow( __in HWND hWnd, __in BOOL bInvert);
此API只闪动窗体一次,显然不是我们想要的结果.
另外一个是FlashWindowEx,函数原型为:
BOOL WINAPI FlashWindowEx( __in PFLASHWINFO pfwi);
参数PFLASHWINFO 声明为:
typedef struct {
UINT cbSize;
HWND hwnd;
DWORD dwFlags;
UINT uCount;
DWORD dwTimeout;
} FLASHWINFO, *PFLASHWINFO;
字段说明:
cbSize结构体FLASHWINFO的大小.
hwnd要闪动的窗体的句柄.窗体可以是打开的也可以是最小化的.
dwFlags
闪动的状态/标志. 此参数可以是以下的值或值的组合(用或操作符"|"组合).
值
含义
FLASHW_ALL
0x00000003
闪动窗体标题和任务栏按钮,等于将此参数设置为:
FLASHW_CAPTION | FLASHW_TRAY.
FLASHW_CAPTION
0x00000001
闪动窗体的标题.
FLASHW_STOP
0
停止闪动.系统将窗体恢复到初始状态.
FLASHW_TIMER
0x00000004
连续不停的闪动,直到此参数被设置为:FLASHW_STOP
FLASHW_TIMERNOFG
0x0000000C
连续不停的闪动,直到窗体用户被激活.通常用法将参数设置为: FLASHW_ALL | FLASHW_TIMERNOFG
FLASHW_TRAY
0x00000002
闪动任务栏按钮
uCount闪动的次数.
dwTimeout闪动频率,单位毫秒. 如果dwTimeout值为0, 函数使用光标的闪动频率.
在C#中引用此API:
1.因为FlashWindowEx的参数是一个FLASHWINFO结构体类型,所以首先按FLASHWINFO格式声明一个结构体:
public struct FLASHWINFO
{
public UInt32 cbSize;
public IntPtr hwnd;
public UInt32 dwFlags;
public UInt32 uCount;
public UInt32 dwTimeout;
}
2. 导入API原型:
[DllImport("user32.dll")]
static extern bool FlashWindowEx(ref FLASHWINFO pwfi);
3.应用API:
private void button1_Click(object sender, EventArgs e)
{
//此处按API中参数dwFlags的取值范围声明常量,方便在使用API时调用,实际应用时可以考虑放到一个专门的文件中
public const UInt32 FLASHW_STOP = 0;
public const UInt32 FLASHW_CAPTION = 1;
public const UInt32 FLASHW_TRAY = 2;
public const UInt32 FLASHW_ALL = 3;
public const UInt32 FLASHW_TIMER = 4;
public const UInt32 FLASHW_TIMERNOFG = 12;
this.WindowState = FormWindowState.Minimized;
//准备参数
FLASHWINFO fInfo = new FLASHWINFO();
fInfo.cbSize = Convert.ToUInt32(Marshal.SizeOf(fInfo));
fInfo.hwnd = this.Handle;
fInfo.dwFlags = FLASHW_ALL | FLASHW_TIMERNOFG;//这里是闪动窗标题和任务栏按钮,直到用户激活窗体
fInfo.uCount = UInt32.MaxValue;
fInfo.dwTimeout = 0;
//调用API
FlashWindowEx(ref fInfo);
}
至此,闪动窗体通知用户的功能实现.
完整代码为:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace FlashWindowEX
{
public struct FLASHWINFO
{
public UInt32 cbSize;
public IntPtr hwnd;
public UInt32 dwFlags;
public UInt32 uCount;
public UInt32 dwTimeout;
}
public partial class Form1 : Form
{
public const UInt32 FLASHW_STOP = 0;
public const UInt32 FLASHW_CAPTION = 1;
public const UInt32 FLASHW_TRAY = 2;
public const UInt32 FLASHW_ALL = 3;
public const UInt32 FLASHW_TIMER = 4;
public const UInt32 FLASHW_TIMERNOFG = 12;
public Form1()
{
InitializeComponent();
}
[DllImport("user32.dll")]
static extern bool FlashWindowEx(ref FLASHWINFO pwfi);
[DllImport("user32.dll")]
static extern bool FlashWindow(IntPtr handle, bool invert);
private void button1_Click(object sender, EventArgs e)
{
this.WindowState = FormWindowState.Minimized;
FLASHWINFO fInfo = new FLASHWINFO();
fInfo.cbSize = Convert.ToUInt32(Marshal.SizeOf(fInfo));
fInfo.hwnd = this.Handle;
fInfo.dwFlags = FLASHW_TRAY | FLASHW_TIMERNOFG;//这里是闪动窗标题和任务栏按钮,直到用户激活窗体
fInfo.uCount = UInt32.MaxValue;
fInfo.dwTimeout = 0;
FlashWindowEx(ref fInfo);
}
}
}