blocks|key|1592778|text|你可以写一个扩展方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1592779|public+static+void+InvokeIfRequired(this+Control+c,+Action<Control>+action)
{
++++if(c.InvokeRequired)
++++{
++++++++c.Invoke(new+Action(()+=>+action(c)));
++++}
++++else
++++{
++++++++action(c);
++++}
}|code-block|syntax|javascript|1592780|并像这样使用它：|1592781|object1.InvokeIfRequired(c+=>+{+c.Visible+=+true;+});|1592782|编辑:正如Simpzon在评论中指出的那样，你也可以将签名更改为：|1592783|public+static+void+InvokeIfRequired<T>(this+T+c,+Action<T>+action)+
++++where+T+:+Control|1592784|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

You could write an extension method:

<pre><code>public static void InvokeIfRequired(this Control c, Action&lt;Control&gt; action)
{
 if(c.InvokeRequired)
 {
 c.Invoke(new Action(() =&gt; action(c)));
 }
 else
 {
 action(c);
 }
}
</code></pre>

And use it like this:

<pre><code>object1.InvokeIfRequired(c =&gt; { c.Visible = true; });
</code></pre>

EDIT: As Simpzon points out in the comments you could also change the signature to:

<pre><code>public static void InvokeIfRequired&lt;T&gt;(this T c, Action&lt;T&gt; action) 
 where T : Control
</code></pre>

blocks|key|1807439|text|下面是我在所有代码中使用的表单。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1807440|private+void+DoGUISwitch()
{+
++++Invoke(+(+MethodInvoker+)+delegate+{
++++++++object1.Visible+=+true;
++++++++object2.Visible+=+false;
++++});
}+|code-block|syntax|javascript|1807441|我是基于博客条目here来实现的。我没有让这种方法让我失败，所以我认为没有理由通过检查InvokeRequired属性来使我的代码复杂化。|offset|length|style|CODE|1807442|希望这能有所帮助。|1807443|entityMap|0|LINK|mutability|MUTABLE|url|http://msmvps.com/blogs/duniho/archive/2008/09/12/msdn-s-canonical-technique-for-using-control-invoke-is-lame.aspx^0|0|0|17|E|8|4|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@$I|Z|J|10|K|L]]|9|@$I|11|J|12|1|13]]|A|$]]|$1|M|3|N|5|6|7|14|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

Here's the form I've been using in all my code.

<pre><code>private void DoGUISwitch()
{ 
 Invoke( ( MethodInvoker ) delegate {
 object1.Visible = true;
 object2.Visible = false;
 });
} 
</code></pre>

I've based this on the blog entry <a href="http://msmvps.com/blogs/duniho/archive/2008/09/12/msdn-s-canonical-technique-for-using-control-invoke-is-lame.aspx" rel="noreferrer">here</a>. I have not had this approach fail me, so I see no reason to complicate my code with a check of the <code>InvokeRequired</code> property.

Hope this helps.

blocks|key|1593020|text|创建一个ThreadSafeInvoke.snippet文件，然后只需选择update语句，右击并选择‘环绕...’。或Ctrl-K%2BS：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1593021|<?xml+version="1.0"+encoding="utf-8"+?>
<CodeSnippet+Format="1.0.0"+xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
++<Header>
++++<Title>ThreadsafeInvoke</Title>
++++<Shortcut></Shortcut>
++++<Description>Wraps+code+in+an+anonymous+method+passed+to+Invoke+for+Thread+safety.</Description>
++++<SnippetTypes>
++++++<SnippetType>SurroundsWith</SnippetType>
++++</SnippetTypes>
++</Header>
++<Snippet>
++++<Code+Language="CSharp">
++++++<![CDATA[
++++++Invoke(+(MethodInvoker)+delegate
++++++{
++++++++++$selected$
++++++});++++++
++++++]]>
++++</Code>
++</Snippet>
</CodeSnippet>|code-block|syntax|javascript|1593022|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Create a ThreadSafeInvoke.snippet file, and then you can just select the update statements, right click and select 'Surround With...' or Ctrl-K+S:

<pre><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt;
&lt;CodeSnippet Format="1.0.0" xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet"&gt;
 &lt;Header&gt;
 &lt;Title&gt;ThreadsafeInvoke&lt;/Title&gt;
 &lt;Shortcut&gt;&lt;/Shortcut&gt;
 &lt;Description&gt;Wraps code in an anonymous method passed to Invoke for Thread safety.&lt;/Description&gt;
 &lt;SnippetTypes&gt;
 &lt;SnippetType&gt;SurroundsWith&lt;/SnippetType&gt;
 &lt;/SnippetTypes&gt;
 &lt;/Header&gt;
 &lt;Snippet&gt;
 &lt;Code Language="CSharp"&gt;
 &lt;![CDATA[
 Invoke( (MethodInvoker) delegate
 {
 $selected$
 }); 
 ]]&gt;
 &lt;/Code&gt;
 &lt;/Snippet&gt;
&lt;/CodeSnippet&gt;
</code></pre>

blocks|key|1593181|text|我宁愿使用方法委托的单个实例，而不是每次都创建一个新实例。在我的例子中，我用来显示进度和来自Backroundworker的(信息/错误)消息，从sql实例复制和转换大型数据。在大约70000次的进度和消息调用之后，我的表单停止工作并显示新的消息。当我开始使用单个全局实例委托时，这并没有发生。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1593182|delegate+void+ShowMessageCallback(string+message);

private+void+Form1_Load(object+sender,+EventArgs+e)
{
++++ShowMessageCallback+showMessageDelegate+=+new+ShowMessageCallback(ShowMessage);
}

private+void+ShowMessage(string+message)
{
++++if+(this.InvokeRequired)
++++++++this.Invoke(showMessageDelegate,+message);
++++else
++++++++labelMessage.Text+=+message;+++++++++++
}

void+Message_OnMessage(object+sender,+Utilities.Message.MessageEventArgs+e)
{
++++ShowMessage(e.Message);
}|code-block|syntax|javascript|1593183|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I'd rather use a single instance of a method Delegate instead of creating a new instance every time.
In my case i used to show progress and (info/error) messages from a Backroundworker copying and casting large data from a sql instance. Everywhile after about 70000 progress and message calls my form stopped working and showing new messages.
This didn't occure when i started using a single global instance delegate.

<pre><code>delegate void ShowMessageCallback(string message);

private void Form1_Load(object sender, EventArgs e)
{
 ShowMessageCallback showMessageDelegate = new ShowMessageCallback(ShowMessage);
}

private void ShowMessage(string message)
{
 if (this.InvokeRequired)
 this.Invoke(showMessageDelegate, message);
 else
 labelMessage.Text = message; 
}

void Message_OnMessage(object sender, Utilities.Message.MessageEventArgs e)
{
 ShowMessage(e.Message);
}
</code></pre>

blocks|key|1807849|text|以下是李、奥利弗和斯蒂芬的答案的改进/合并版本。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1807850|public+delegate+void+InvokeIfRequiredDelegate<T>(T+obj)
++++where+T+:+ISynchronizeInvoke;

public+static+void+InvokeIfRequired<T>(this+T+obj,+InvokeIfRequiredDelegate<T>+action)
++++where+T+:+ISynchronizeInvoke
{
++++if+(obj.InvokeRequired)
++++{
++++++++obj.Invoke(action,+new+object[]+{+obj+});
++++}
++++else
++++{
++++++++action(obj);
++++}
}+|code-block|syntax|javascript|1807851|该模板允许灵活和较少强制转换的代码，更具可读性，而专用的委托提供了效率。|1807852|progressBar1.InvokeIfRequired(o+=>+
{
++++o.Style+=+ProgressBarStyle.Marquee;
++++o.MarqueeAnimationSpeed+=+40;
});|1807853|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Here's an improved/combined version of Lee's, Oliver's and Stephan's answers.

<pre><code>public delegate void InvokeIfRequiredDelegate&lt;T&gt;(T obj)
 where T : ISynchronizeInvoke;

public static void InvokeIfRequired&lt;T&gt;(this T obj, InvokeIfRequiredDelegate&lt;T&gt; action)
 where T : ISynchronizeInvoke
{
 if (obj.InvokeRequired)
 {
 obj.Invoke(action, new object[] { obj });
 }
 else
 {
 action(obj);
 }
} 
</code></pre>

The template allows for flexible and cast-less code which is much more readable while the dedicated delegate provides efficiency.

<pre><code>progressBar1.InvokeIfRequired(o =&gt; 
{
 o.Style = ProgressBarStyle.Marquee;
 o.MarqueeAnimationSpeed = 40;
});
</code></pre>

blocks|key|1807998|text|我喜欢做一些不同的事情，如果需要一个动作，我喜欢叫“我自己”，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1807999|++++private+void+AddRowToListView(ScannerRow+row,+bool+suspend)
++++{
++++++++if+(IsFormClosing)
++++++++++++return;

++++++++if+(this.InvokeRequired)
++++++++{
++++++++++++var+A+=+new+Action(()+=>+AddRowToListView(row,+suspend));
++++++++++++this.Invoke(A);
++++++++++++return;
++++++++}
+++++++++//as+of+here+the+Code+is+thread-safe|code-block|syntax|javascript|1808000|这是一个很方便的模式，IsFormClosing是我在关闭表单时设置为True的字段，因为可能有一些后台线程仍在运行……|1808001|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I Kind of like to do it a bit different, i like to call "myself" if needed with an Action, 

<pre><code> private void AddRowToListView(ScannerRow row, bool suspend)
 {
 if (IsFormClosing)
 return;

 if (this.InvokeRequired)
 {
 var A = new Action(() =&gt; AddRowToListView(row, suspend));
 this.Invoke(A);
 return;
 }
 //as of here the Code is thread-safe
</code></pre>

this is a handy pattern, the IsFormClosing is a field that i set to True when I am closing my form as there might be some background threads that are still running...

blocks|key|1808003|text|用法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1808004|control.InvokeIfRequired(c+=>+c.Visible+=+false);

return+control.InvokeIfRequired(c+=>+{
++++c.Visible+=+value

++++return+c.Visible;
});|code-block|syntax|javascript|1808005|代码：|1808006|using+System;
using+System.ComponentModel;

namespace+Extensions
{
++++public+static+class+SynchronizeInvokeExtensions
++++{
++++++++public+static+void+InvokeIfRequired<T>(this+T+obj,+Action<T>+action)
++++++++++++where+T+:+ISynchronizeInvoke
++++++++{
++++++++++++if+(obj.InvokeRequired)
++++++++++++{
++++++++++++++++obj.Invoke(action,+new+object[]+{+obj+});
++++++++++++}
++++++++++++else
++++++++++++{
++++++++++++++++action(obj);
++++++++++++}
++++++++}

++++++++public+static+TOut+InvokeIfRequired<TIn,+TOut>(this+TIn+obj,+Func<TIn,+TOut>+func)+
++++++++++++where+TIn+:+ISynchronizeInvoke
++++++++{
++++++++++++return+obj.InvokeRequired
++++++++++++++++?+(TOut)obj.Invoke(func,+new+object[]+{+obj+})
++++++++++++++++:+func(obj);
++++++++}
++++}
}|1808007|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Usage:

<pre><code>control.InvokeIfRequired(c =&gt; c.Visible = false);

return control.InvokeIfRequired(c =&gt; {
 c.Visible = value

 return c.Visible;
});
</code></pre>

Code:

<pre class="lang-cs prettyprint-override"><code>using System;
using System.ComponentModel;

namespace Extensions
{
 public static class SynchronizeInvokeExtensions
 {
 public static void InvokeIfRequired&lt;T&gt;(this T obj, Action&lt;T&gt; action)
 where T : ISynchronizeInvoke
 {
 if (obj.InvokeRequired)
 {
 obj.Invoke(action, new object[] { obj });
 }
 else
 {
 action(obj);
 }
 }

 public static TOut InvokeIfRequired&lt;TIn, TOut&gt;(this TIn obj, Func&lt;TIn, TOut&gt; func) 
 where TIn : ISynchronizeInvoke
 {
 return obj.InvokeRequired
 ? (TOut)obj.Invoke(func, new object[] { obj })
 : func(obj);
 }
 }
}
</code></pre>

I have become painfully aware of just how often one needs to write the following code pattern in event-driven GUI code, where

<pre><code>private void DoGUISwitch() {
 // cruisin for a bruisin' through exception city
 object1.Visible = true;
 object2.Visible = false;
}
</code></pre>

becomes:

<pre><code>private void DoGUISwitch() {
 if (object1.InvokeRequired) {
 object1.Invoke(new MethodInvoker(() =&gt; { DoGUISwitch(); }));
 } else {
 object1.Visible = true;
 object2.Visible = false;
 }
}
</code></pre>

This is an awkward pattern in C#, both to remember, and to type. Has anyone come up with some sort of shortcut or construct that automates this to a degree? It'd be cool if there was a way to attach a function to objects that does this check without having to go through all this extra work, like a <code>object1.InvokeIfNecessary.visible = true</code> type shortcut.

Previous <a href="https://stackoverflow.com/questions/747210/whats-wrong-with-calling-invoke-regardless-of-invokerequired">answers</a> have discussed the impracticality of just calling Invoke() every time, and even then the Invoke() syntax is both inefficient and still awkward to deal with.

So, has anyone figured out any shortcuts?

Automating the InvokeRequired code pattern

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

文章

问答

视频

学习中心

腾讯云实验室

直播

竞赛

腾讯云架构师技术同盟交流圈

腾讯云数据库专区

腾讯云顾问专区

腾讯云原生专区

腾讯混元专区

腾讯云TCE专区

腾讯云Lighthouse专区

腾讯云HAI专区

腾讯云Edgeone专区

腾讯云存储专区

腾讯云智能专区

腾讯轻联专区 

腾讯云开发专区

TAPD专区

腾讯轻量云游戏服专区

腾讯云最具价值专家

腾讯云架构师技术同盟

腾讯云创作之星

腾讯云开发者先锋 

腾讯云代码助手

CODING DevOps

Cloud Studio

SDK中心

API中心

命令行工具

private void DoGUISwitch() {    // cruisin for a bruisin' through exception city    object1.Visible = true;    object2.Visible = false;}变成：private void DoGUISwi...

问自动化InvokeRequired代码模式
EN

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问自动化InvokeRequired代码模式EN