短消息提示Toast:
用于呈现一条短消息，提示完成后即可自动消失；
特点：
① 弹出式窗口；
② 短文本，可以折行显示；
③ 根据文本长度，自动调整大小；
④ 约1.5后，自动消失；
在Winform中，所有的窗口都用Form实现，比如：
① 常规窗口Window;
② 对话框窗口Dialog；
③ 悬浮窗口FloatWindow;
④ 工具提示Tooltip;
⑤ 弹出式窗口Popup（如菜单窗口、下拉列表窗口）；
自定义一个Form类，即可定义一个窗口
public class myToast:Form
{
}
本窗口不需要边框，位置和大小都是自己控制的。
创建并显示窗口
myToast toast=new myToast();
toast.ShowMessage("This is a totas!");
子窗体代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 弹窗提示
{
public partial class Toast : Form
{
private string message;
public Toast()
{
//无边框
this.FormBorderStyle = FormBorderStyle.None;
//背景白色
this.BackColor = Color.White;
}
public void ShowMessage(string message)
{
this.message = message;
//手动指定位置
this.StartPosition = FormStartPosition.Manual;
this.Location = new Point(0, 0);
this.Size = new Size(300, 100);
//显示窗口
this.Show();
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Graphics g = e.Graphics;
int w = this.Width, h = this.Height;
Rectangle rect = new Rectangle(0, 0, w, h);
rect.Inflate(-4, -4);
//平滑绘制，反锯齿
g.SmoothingMode = SmoothingMode.HighQuality;
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
if(message!=null)
{
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
Brush brush = new SolidBrush(Color.Black);
g.DrawString(message, this.Font, brush, rect, sf);
brush.Dispose();
}
}
}
}父窗体代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 弹窗提示
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Toast toast = new Toast();
toast.ShowMessage("This is a toast!");
}
}
}toast窗口显示时，相当于主窗口位置居中。
① 找到主窗口，得到主窗口的位置；
② 计算toast窗口的位置；
toast窗口显示时，不剥夺主窗口的焦点，需要重写ShowWithoutActivation
protected override bool ShowWithoutActivation
{
get
{
return true;
}
}
① 已知一个控件Control,可以得到它所在的窗口;
Form form=ctrl.FindForm();
子窗体代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 窗口位置
{
public partial class Toast : Form
{
private string message;
public Toast()
{
this.FormBorderStyle = FormBorderStyle.None;
this.BackColor = Color.White;
this.ShowInTaskbar = false;
}
//owner 可以是子窗口也可以是控件
public void ShowMessage(Control owner,string message)
{
this.message = message;
this.StartPosition = FormStartPosition.Manual;
this.Size = new Size(300, 100);
//找到owner所在的顶级窗口
Form form = owner.FindForm();
this.Owner = form;
//使toast窗口相对主窗口居中
Rectangle fr = new Rectangle(form.Location, form.Size);
int x = fr.X + (fr.Width - this.Width) / 2;
int y = fr.Y + (fr.Width - this.Height) / 2;
this.Location = new Point(x, y);
this.Show();
}
//焦点控制：本窗口不剥夺主窗口的焦点
//否则，当toast窗口激活时，主窗口焦点被剥夺
protected override bool ShowWithoutActivation
{
get { return true; }
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Graphics g = e.Graphics;
int w = this.Width, h = this.Height;
Rectangle rect = new Rectangle(0, 0, w, h);
rect.Inflate(-4, -4);
//平滑绘制，反锯齿
g.SmoothingMode = SmoothingMode.HighQuality;
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
if(message!=null)
{
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
Brush brush = new SolidBrush(Color.Black);
g.DrawString(message, this.Font, brush, rect, sf);
brush.Dispose();
}
}
}
}父窗体代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 窗口位置
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Toast toast = new Toast();
toast.ShowMessage(button1, "中国人民解放军！");
}
}
}Toast的窗口的大小，应该根据消息长度来调整，比如：
toast.ShowMessage(button1,"成功"); toast.ShowMessage(button1,"思密达"); toast.ShowMessage(button1,"编程是一种艺术");
使用Graphics.MeasureString()可以测算文本的尺寸
Graphics g=this.CreateGraphics(); SizeF size=g.MeasureString(str,this.Font,300); g.Dispose();
注意，临时创建的Graphics用完之后需要手工销毁。
