winform 多线程如何刷新控件，在线等.....

[str345]

在一个form中有listbox控件，在form启动后，自动执行多线程，在线程中不时刷新listbox控件。在常见的例子中，多线程是一个form类中函数，所以在多线程中可以看见listbox，之后进行委托即可，但是我现在要执行的多线程是另一个类中的函数（添加了新类mythread），在这个类中listbox不可见，无法委托，要是form n =new form(); xxx+ = new mydelegate(n.setlistbox);，不是刷新原来的listbox控件，是新建一个form （n)，刷新的是他的控件，如何解决，谢谢！！！！！

[kkun_3yue3]

写得可够乱的,把那个Listbox封装成一个静态属性试试
public static ListBox YourListBox {get { return this.listbox1; }}
多线程中调用该属性

[str345]

to: jingshuaizh
--------------------------------
form1.setlistbox 不是静态函数，无法调用！！！！！

[str345]

kkun_3yue3
－－－－－－－－－－－－－－－－－－－－－－－－－
我希望用委托实现？静态的估计没事，但是看着不舒服！！！

[sugarche]

那你在mythread类里面写一个静态的委托
在form里面指向setlistbox方法就可以了

[CGabriel]

后台线程问主线程要一个 Synchronization， 在需要更新主界面的时候， 后台线程使用事件通知主线程，同时把Synchronization 作为事件参数封装进去。

主线程响应了后台线程的事件，就可以通过参数 Synchronization, 线程安全地更新主界面

[utopia54]

UP

[bluelism]

我也遇到同样的问题 郁闷好几天了！ 关注~~~~

[bluelism]

[Quote=引用 1 楼 jingshuaizh 的回复:]

直接调用 form1.setlistbox 不可以么 不用new 一个form 用原来的form对象
[/Quote]
我想更新的是textBox ， MainForm.textBox1.Text = showData; 编译的时候会出现 “非静态的字段、方法或属性“MainForm.textBox1”要求对象引用“ 的错误提示~~

[卧_槽]

[Quote=引用 10 楼 bluelism 的回复:]

引用 1 楼 jingshuaizh 的回复:

直接调用 form1.setlistbox 不可以么 不用new 一个form 用原来的form对象

我想更新的是textBox ， MainForm.textBox1.Text = showData; 编译的时候会出现 “非静态的字段、方法或属性“MainForm.textBox1”要求对象引用“ 的错误提示~~
[/Quote]
你的form对象要传递到后台线程里才行。MainForm只是类，不是对象。

[铛铛]

顶1楼

[c_t0427]

msdn里面有个关于线程安全的例子。不知道是不是楼主想要的。

using System;
using System.ComponentModel;
using System.Threading;
using System.Windows.Forms;

namespace CrossThreadDemo
{
	public class Form1 : Form
	{
		// This delegate enables asynchronous calls for setting
		// the text property on a TextBox control.
		delegate void SetTextCallback(string text);

		// This thread is used to demonstrate both thread-safe and
		// unsafe ways to call a Windows Forms control.
		private Thread demoThread = null;

		// This BackgroundWorker is used to demonstrate the 
		// preferred way of performing asynchronous operations.
		private BackgroundWorker backgroundWorker1;

		private TextBox textBox1;
		private Button setTextUnsafeBtn;
		private Button setTextSafeBtn;
		private Button setTextBackgroundWorkerBtn;

		private System.ComponentModel.IContainer components = null;

		public Form1()
		{
			InitializeComponent();
		}

		protected override void Dispose(bool disposing)
		{
			if (disposing && (components != null))
			{
				components.Dispose();
			}
			base.Dispose(disposing);
		}

		// This event handler creates a thread that calls a 
		// Windows Forms control in an unsafe way.
		private void setTextUnsafeBtn_Click(
			object sender, 
			EventArgs e)
		{
			this.demoThread = 
				new Thread(new ThreadStart(this.ThreadProcUnsafe));

			this.demoThread.Start();
		}

		// This method is executed on the worker thread and makes
		// an unsafe call on the TextBox control.
		private void ThreadProcUnsafe()
		{
			this.textBox1.Text = "This text was set unsafely.";
		}

		// This event handler creates a thread that calls a 
		// Windows Forms control in a thread-safe way.
		private void setTextSafeBtn_Click(
			object sender, 
			EventArgs e)
		{
			this.demoThread = 
				new Thread(new ThreadStart(this.ThreadProcSafe));

			this.demoThread.Start();
		}

		// This method is executed on the worker thread and makes
		// a thread-safe call on the TextBox control.
		private void ThreadProcSafe()
		{
			this.SetText("This text was set safely.");
		}

		// This method demonstrates a pattern for making thread-safe
		// calls on a Windows Forms control. 
		//
		// If the calling thread is different from the thread that
		// created the TextBox control, this method creates a
		// SetTextCallback and calls itself asynchronously using the
		// Invoke method.
		//
		// If the calling thread is the same as the thread that created
		// the TextBox control, the Text property is set directly. 

		private void SetText(string text)
		{
			// InvokeRequired required compares the thread ID of the
			// calling thread to the thread ID of the creating thread.
			// If these threads are different, it returns true.
			if (this.textBox1.InvokeRequired)
			{	
				SetTextCallback d = new SetTextCallback(SetText);
				this.Invoke(d, new object[] { text });
			}
			else
			{
				this.textBox1.Text = text;
			}
		}

		// This event handler starts the form's 
		// BackgroundWorker by calling RunWorkerAsync.
		//
		// The Text property of the TextBox control is set
		// when the BackgroundWorker raises the RunWorkerCompleted
		// event.
		private void setTextBackgroundWorkerBtn_Click(
			object sender, 
			EventArgs e)
		{
			this.backgroundWorker1.RunWorkerAsync();
		}
		
		// This event handler sets the Text property of the TextBox
		// control. It is called on the thread that created the 
		// TextBox control, so the call is thread-safe.
		//
		// BackgroundWorker is the preferred way to perform asynchronous
		// operations.

		private void backgroundWorker1_RunWorkerCompleted(
			object sender, 
			RunWorkerCompletedEventArgs e)
		{
			this.textBox1.Text = 
				"This text was set safely by BackgroundWorker.";
		}

		#region Windows Form Designer generated code

		private void InitializeComponent()
		{
			this.textBox1 = new System.Windows.Forms.TextBox();
			this.setTextUnsafeBtn = new System.Windows.Forms.Button();
			this.setTextSafeBtn = new System.Windows.Forms.Button();
			this.setTextBackgroundWorkerBtn = new System.Windows.Forms.Button();
			this.backgroundWorker1 = new System.ComponentModel.BackgroundWorker();
			this.SuspendLayout();
			// 
			// textBox1
			// 
			this.textBox1.Location = new System.Drawing.Point(12, 12);
			this.textBox1.Name = "textBox1";
			this.textBox1.Size = new System.Drawing.Size(240, 20);
			this.textBox1.TabIndex = 0;
			// 
			// setTextUnsafeBtn
			// 
			this.setTextUnsafeBtn.Location = new System.Drawing.Point(15, 55);
			this.setTextUnsafeBtn.Name = "setTextUnsafeBtn";
			this.setTextUnsafeBtn.TabIndex = 1;
			this.setTextUnsafeBtn.Text = "Unsafe Call";
			this.setTextUnsafeBtn.Click += new System.EventHandler(this.setTextUnsafeBtn_Click);
			// 
			// setTextSafeBtn
			// 
			this.setTextSafeBtn.Location = new System.Drawing.Point(96, 55);
			this.setTextSafeBtn.Name = "setTextSafeBtn";
			this.setTextSafeBtn.TabIndex = 2;
			this.setTextSafeBtn.Text = "Safe Call";
			this.setTextSafeBtn.Click += new System.EventHandler(this.setTextSafeBtn_Click);
			// 
			// setTextBackgroundWorkerBtn
			// 
			this.setTextBackgroundWorkerBtn.Location = new System.Drawing.Point(177, 55);
			this.setTextBackgroundWorkerBtn.Name = "setTextBackgroundWorkerBtn";
			this.setTextBackgroundWorkerBtn.TabIndex = 3;
			this.setTextBackgroundWorkerBtn.Text = "Safe BW Call";
			this.setTextBackgroundWorkerBtn.Click += new System.EventHandler(this.setTextBackgroundWorkerBtn_Click);
			// 
			// backgroundWorker1
			// 
			this.backgroundWorker1.RunWorkerCompleted += new System.ComponentModel.RunWorkerCompletedEventHandler(this.backgroundWorker1_RunWorkerCompleted);
			// 
			// Form1
			// 
			this.ClientSize = new System.Drawing.Size(268, 96);
			this.Controls.Add(this.setTextBackgroundWorkerBtn);
			this.Controls.Add(this.setTextSafeBtn);
			this.Controls.Add(this.setTextUnsafeBtn);
			this.Controls.Add(this.textBox1);
			this.Name = "Form1";
			this.Text = "Form1";
			this.ResumeLayout(false);
			this.PerformLayout();

		}

		#endregion


		[STAThread]
		static void Main()
		{
			Application.EnableVisualStyles();
			Application.Run(new Form1());
		}

	}
}

[songxiangzaiya]

每天回帖既有十分可用。

[jyx20150104]

[Quote=引用 1 楼 jingshuaizh 的回复:]

直接调用 form1.setlistbox 不可以么 不用new 一个form 用原来的form对象
另外 还要做些别的

VS2005 多线程问题--窗体中的线程安全调用 part1(2008-08-26 11:19:02)标签：杂谈 分类：ASP.NET/C#
访问 Windows 窗体控件本质上不是线程安全的。如果有两个或多个线程操作某一控件的状态，则可能会迫使该控件进入一……
[/Quote]

VS2010中Control.CheckForIllegalCrossThreadCalls = false就是这样的；

[jyx20150104]

建议用委托；如果数据量大，就用多线程，使UI线程和数据处理分开

[白虹李李]

看到这个帖子很难过。
第一是我也遇到了这个问题。
第二是没看到解决办法。
楼上众多高手都讲述了如何在Form类里启动一个线程并且安全的访问Form上的一个控件。。。
this.textBox1
可惜的是，这个所谓的线程也是在这个类里的，它认识textBox1。

要是在另一个类里怎么办？
根本就没有this.textBox1啊

[白虹李李]

楼主不知道解决了没有啊？

[cy_paul]

使用BackgroundWorder控件后台运行，并在它的ProgressChanged 事件和RunWorkerCompleted 事件里与其它控件互动。这才是正道。
多线程什么的，根本无法调试

[lzzheng0517]

控件可以直接传递过去的吧？

[bwangel]

在线程执行中，是无法直接访问控件的，要用Invoke

[yandy2012]

使用 托管啊 ，如果多线程的话