blocks|key|492239|text|你们很亲密：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|492240|<ChildComponent+Item="someModel"+T="SomeModel"+DeleteCallback="OnDeleteSomeModel"+/>

@code+{
++++SomeModel+someModel+=+new+SomeModel();

++++void+OnDeleteSomeModel(SomeModel+someModel)
++++{
++++++++...
++++}
}|code-block|syntax|javascript|492241|EventCallback使用泛型类型，如果不将该类型传递给组件，则blazor无法推断该类型。|492242|这意味着，如果您有一个EventCallback<T>，您需要将T的值传递给组件，例如T="SomeType"。|offset|length|style|CODE|492243|entityMap^0|0|0|0|B|G|W|1|17|C|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]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|T|8|@$K|U|L|V|M|N]|$K|W|L|X|M|N]|$K|Y|L|Z|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|P|$]]

You were close:
<pre><code>&lt;ChildComponent Item=&quot;someModel&quot; T=&quot;SomeModel&quot; DeleteCallback=&quot;OnDeleteSomeModel&quot; /&gt;

@code {
 SomeModel someModel = new SomeModel();

 void OnDeleteSomeModel(SomeModel someModel)
 {
 ...
 }
}
</code></pre>
The EventCallback uses a generic type and blazor cannot infer it if you don't pass the type to the component.
This means that if you have a <code>EventCallback&lt;T&gt;</code> you need to pass the value of <code>T</code> to the component e.g. <code>T=&quot;SomeType&quot;</code>.

blocks|key|487645|text|以下语法适用于我：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|487646|//+in+the+component+(C#):
[Parameter]
public+EventCallback<MovingEventArgs>+OnMoving+{+get;+set;+}

//+on+the+using+side+(Razor):
OnMoving="(Component.MovingEventArgs+o)+=>+OnMoving(o)"

//+on+the+using+side+(C#):
protected+void+OnMoving(+Component.MovingEventArgs+e+)+{
}|code-block|syntax|javascript|487647|似乎发生了变化，这些文件并不是最新的。此事件还使用自定义事件参数。|487648|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|$]]

The following syntax worked for me:
<pre><code>// in the component (C#):
[Parameter]
public EventCallback&lt;MovingEventArgs&gt; OnMoving { get; set; }

// on the using side (Razor):
OnMoving=&quot;(Component.MovingEventArgs o) =&gt; OnMoving(o)&quot;

// on the using side (C#):
protected void OnMoving( Component.MovingEventArgs e ) {
}
</code></pre>
There seems to have been a change and the documentation is not up to date.
This event is also using custom event arguments.

blocks|key|171939|text|在我的例子中，我声明了一个可为空的EventCallback?+--您不能这样做。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|171940|entityMap^0|H|E|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

In my case I declared a nullable <code>EventCallback?</code> - you can't do that.

blocks|key|487658|text|我已经经历了语法上的问题，但仍然会出现这个错误。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|487659|重新启动Visual+2019为我解决了这个问题。仅仅清洁和重建是不够的。|487660|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

I've experienced that the syntax was spot on and still getting this error.
Restarting Visual Studio 2019 solved the problem for me. Cleaning and rebuilding was not enough.

blocks|key|171997|text|由于某种原因，Visual保留了我以前使用过的签名。清理、重新启动、清空bin/obj文件夹等都不起作用。我不得不将重命名为，这个方法对我很有用。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|171998|entityMap^0|1M|4|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

For some reason Visual Studio kept a previous signature I had used. Cleaning, restarting, emptying bin/obj folders etc did not work. I had to rename the method, which worked for me.

blocks|key|1047011|text|在我的例子中，当我手动定义@typeparam+(而不是通过推断)(TItem="int")时，这个问题得到了解决。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1047012|<MyComponent+TItem="int"+OnChange="Component_Changed"+/>|code-block|syntax|javascript|1047013|entityMap^0|D|A|Y|B|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

In my case, the problem solved when I defined the <code>@typeparam</code> manually(not by inference)(<code>TItem=&quot;int&quot;</code>).
<pre><code>&lt;MyComponent TItem=&quot;int&quot; OnChange=&quot;Component_Changed&quot; /&gt;
</code></pre>

blocks|key|487692|text|对于任何与MudBlazor+MudTable进行斗争的人，我发现这种方法是有效的，使用@，并且不向commit函数传递任何参数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|487693|<MudTable+T="POCO"+Items="@MyState.POCOs"+
++++++++++++++++++++++++++++++@bind-SelectedItem="_selectedPOCO"++
++++++++++++++++++++++++++++++OnCommitEditClick="@(()+=>+commitPOCO())"
++++++++++++++++++++++++++++++CommitEditTooltip="Save+Changes?">
@code+{
++++private+POCO+_selectedPOCO;

++++private+async+void+commitPOCO()
++++{
++++++++//+all+the+changed+values+are+in+_selectedPOCO
++++++++...
++++}|code-block|syntax|javascript|487694|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|$]]

For anyone fighting this with the MudBlazor MudTable I found this worked use @bind-SelectedItem and don't pass any parameters to the commit function.
<pre><code>&lt;MudTable T=&quot;POCO&quot; Items=&quot;@MyState.POCOs&quot; 
 @bind-SelectedItem=&quot;_selectedPOCO&quot; 
 OnCommitEditClick=&quot;@(() =&gt; commitPOCO())&quot;
 CommitEditTooltip=&quot;Save Changes?&quot;&gt;
@code {
 private POCO _selectedPOCO;

 private async void commitPOCO()
 {
 // all the changed values are in _selectedPOCO
 ...
 }
</code></pre>

blocks|key|172094|text|好吧我只是花了几个小时想办法解决这个问题。最后，问题是我在项目中进行了同步融合，我已经显式地定义了事件回调参数的名称空间(在我的例子中是子组件中的Microsoft.AspNetCore.Components.ChangeEventArgs+)，然后创建一个异步方法将数据传回父组件。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|172095|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Okay I just spent hours trying to figure this out. Turns out on my end the problem was I have sync fusion in the project and I had explicitly define the name space of the Event call back arguments which in my case were Microsoft.AspNetCore.Components.ChangeEventArgs in the child component and then creating an async method to pass back data to the parent.

blocks|key|172175|text|在我的例子中，不管我做什么，这都是其他几十个人中的一个幻影错误。这意味着我仍然可以建立和运行一个没有问题的解决方案，尽管有这么多的问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|172176|帮助我的是这个解决方案：https://stackoverflow.com/a/66219566/1215913|offset|length|172177|然而，经过几个小时的挖掘，我终于找到了一个解决方案。为了消除幻影错误，我关闭了Visual，删除了以下文件夹中的文件，然后重新打开解决方案:+C:\Users\AppData\Local\Temp\VSFeedbackIntelliCodeLogs\Suggestions\|172178|172179|唯一的区别是我删除了所有以VS+(C:\Users\<Username>\AppData\Local\Temp\VS*)开头的文件夹，因为在他的帖子中没有这个确切的路径。|style|CODE|172180|这似乎是Blazor和IntelliSense中的一些常见问题。我还经常看到自动格式化程序无法正确格式化razor代码(文本缩进是一团糟)。|172181|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/66219566/1215913^0|0|C|18|0|0|0|0|H|16|0|4|6|B|C|1G|5|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@$D|Y|E|Z|1|10]]|A|$]]|$1|F|3|G|5|6|7|11|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|13|8|@$D|14|E|15|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|16|8|@$D|17|E|18|K|L]|$D|19|E|1A|K|L]|$D|1B|E|1C|K|L]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

In my case it was a phantom error among tens others that never went away no matter what I do. Meaning I could still build and run a solution without problems, despite so many erorrs.
What helped me was this solution: <a href="https://stackoverflow.com/a/66219566/1215913">https://stackoverflow.com/a/66219566/1215913</a>
<blockquote>
However, I finally found a solution after a few hours of digging. To
get rid of the phantom errors I closed Visual Studio, deleted the
files in the following folder, and then re-opened the solution:
C:\Users&lt;Username&gt;\AppData\Local\Temp\VSFeedbackIntelliCodeLogs\Suggestions\
</blockquote>
The only difference is I removed all of the folders that start with VS (<code>C:\Users\&lt;Username&gt;\AppData\Local\Temp\VS*</code>) since there was no this exact path as @rovert mentions in his post.
This seems to be some common problem with <code>Blazor</code> and <code>IntelliSense</code>. I also often see that auto-formatter fails to correctly format the <code>razor</code> code (text indentations are a mess).

I have a parent component and a child component with an event callback where I want it to pass back a type of T.
The issue I'm having is that I have an error about converting
<blockquote>
MethodGroup to EventCallback.
</blockquote>
If I convert this to using an <code>Action</code> then it works, but I can't do it async which isn't ideal.
Any ideas what I'm doing wrong?
<hr />
Parent
<pre><code>&lt;Child DeleteCallback=&quot;@OnDelete&quot;&gt;&lt;/Child&gt;

public async Task OnDelete(T item)
{ ... }
</code></pre>
Child
<pre><code>@typeparam T

[Parameter]
public EventCallback&lt;T&gt; DeleteCallback { get; set; }

 &lt;a @onclick=&quot;() =&gt; DeleteCallback.InvokeAsync(item)&quot;&gt;&lt;/a&gt;
</code></pre>
I've added a repo here explaining the problem. Looking at the Issues for Blazor, this should;ve been fixed in 2019. <a href="https://github.com/scott-david-walker/EventCallbackError" rel="noreferrer">https://github.com/scott-david-walker/EventCallbackError</a>

Blazor - cannot convert from 'method group' to 'EventCallback'

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。

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我有一个父组件和一个具有事件回调的子组件，在其中我希望它传回一种类型的T。我遇到的问题是我在转换 MethodGroup to EventCallback。如果我将它转换为使用Action，那么它就能工作，但我不能这样做，这并不理想。知道我做错什么了吗？父级<Child DeleteCallback="@OnDelet...

问Blazor无法从“方法组”转换为“EventCallback”
EN

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问Blazor无法从“方法组”转换为“EventCallback”EN