BeginInvoke 提高UI的响应速度

代码
 1using System;
 2using System.Collections.Generic;
 3using System.ComponentModel;
 4using System.Data;
 5using System.Drawing;
 6using System.Text;
 7using System.Windows.Forms;
 8
 9using System.Threading;
10
11namespace CSharpGeriac
12{
13    public partial class Form1 : Form
14    {
15        public Form1()
16        {
17            InitializeComponent();
18
19            Thread t = new Thread(new ThreadStart(ChangeLabel));
20            t.Start();
21        }
22
23        private void ChangeLabel()
24        {
25            for (int i = 0; i < 100; ++i)
26            {
27                SetLabelText(i);
28                Thread.Sleep(1000);
29            }
30        }
31
32        private void SetLabelText(int number)
33        {
34            // label.Text = number.ToString();
35            // Do NOT do this, as we are on a different thread.
36
37            // Check if we need to call BeginInvoke.
38            if (this.InvokeRequired)
39            {
40                // Pass the same function to BeginInvoke,
41                // but the call would come on the correct
42                // thread and InvokeRequired will be false.
43                this.BeginInvoke(new SetLabelTextDelegate(SetLabelText),
44                                                 new object[] { number });
45
46                return;
47            }
48
49            label1.Text = number.ToString();
50
51        }
52
53        private delegate void SetLabelTextDelegate(int number);
54    }
55}

Another Example:

别一例子
 1using System;
 2using System.Drawing;
 3using System.Threading;
 4using System.Windows.Forms;
 5
 6class Program : Form
 7{
 8    private System.Windows.Forms.ProgressBar _ProgressBar;
 9
10    [STAThread]
11    static void Main()
12    {
13        Application.Run(new Program());
14    }
15
16    public Program()
17    {
18        InitializeComponent();
19        ThreadStart threadStart = Increment;
20        threadStart.BeginInvoke(null, null);
21    }
22
23    void UpdateProgressBar()
24    {
25        if (_ProgressBar.InvokeRequired)
26        {
27            MethodInvoker updateProgressBar = UpdateProgressBar;
28            _ProgressBar.Invoke(updateProgressBar);
29        }
30        else
31        {
32            _ProgressBar.Increment(1);
33        }
34    }
35
36    private void Increment()
37    {
38        for (int i = 0; i < 100; i++)
39        {
40            UpdateProgressBar();
41            Thread.Sleep(100);
42        }
43        if (InvokeRequired)
44        {
45            // Close cannot be called directly from             
46            // a non-UI thread.                                  
47            Invoke(new MethodInvoker(Close));
48        }
49        else
50        {
51            Close();
52        }
53    }
54
55    private void InitializeComponent()
56    {
57        _ProgressBar = new ProgressBar();
58        SuspendLayout();
59
60        _ProgressBar.Location = new Point(13, 17);
61        _ProgressBar.Size = new Size(267, 19);
62
63        ClientSize = new Size(292, 53);
64        Controls.Add(this._ProgressBar);
65        Text = "Multithreading in Windows Forms";
66        ResumeLayout(false);
67    }
68}