.NET3.5下用Lambda简化跨线程访问窗体控件,避免繁复的delegate,Invoke(转)

最新推荐文章于 2022-08-09 14:49:14 发布

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最新推荐文章于 2022-08-09 14:49:14 发布

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原文链接：http://www.cnblogs.com/arongbest/archive/2011/08/03/2126277.html

本文讨论了在WindowsForms应用中遇到的线程安全问题，并提供了通过使用SafeInvoke方法来解决该问题的方法，避免了Cross-thread operation not valid错误。

1、错误的代码是：

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;

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private string blog = "http://www.chenjiliang.com/";

        private void Form1_Load(object sender, EventArgs e)
        {
            new System.Threading.Thread(ShowTime).Start();
        }

        private void ShowTime()
        {
            textBox1.Text = DateTime.Now.ToString();
        }
    }
}

会看到Cross-thread operation not valid: Control 'textBox1' accessed from a thread other than the thread it was created on.的错误

2、增加一个Public static 类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication5
{
    public static class ControlExtention
    {
        public delegate void InvokeHandler();

        public static void SafeInvoke(this Control control, InvokeHandler handler)
        {
            if (control.InvokeRequired)
            {
                control.Invoke(handler);
            }
            else
            {
                handler();
            }
        }
    }
}

3、build

4、这样写就好啦

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;

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private string s = "http://www.chenjiliang.com/";

        private void Form1_Load(object sender, EventArgs e)
        {
            new System.Threading.Thread(ShowTime).Start();
        }

        private void ShowTime()
        {
            this.SafeInvoke(() =>
            {
                textBox1.Text = DateTime.Now.ToString();
            });
        }
    }
}

转载于:https://www.cnblogs.com/arongbest/archive/2011/08/03/2126277.html