blocks|key|1495381|text|您的特定情况可以简单地更正为正常工作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495382|<script+type="text/javascript">
++var+myButton+=+document.getElementById("myButton");
++var+myMessage+=+"it's+working";
++myButton.onclick+=+function()+{+alert(myMessage);+};
</script>|code-block|syntax|javascript|1495383|这个例子是可行的，因为创建的匿名函数作为元素的处理程序可以访问在创建它的上下文中定义的变量。|1495384|对于记录，处理程序(通过设置onxxx属性指定)期望单个参数接受由DOM传递的事件对象，并且您不能在其中强制传递其他参数|1495385|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]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<p>Your specific case can simply be corrected to be working:</p>

<pre><code>&lt;script type="text/javascript"&gt;
  var myButton = document.getElementById("myButton");
  var myMessage = "it's working";
  myButton.onclick = function() { alert(myMessage); };
&lt;/script&gt;
</code></pre>

<p>This example will work because the anonymous function created and assigned as a handler to element will have access to variables defined in the context where it was created.</p>

<p>For the record, a handler (that you assign through setting onxxx property) expects single argument to take that is event object being passed by the DOM, and you cannot force passing other argument in there</p>


blocks|key|1710503|text|通过从匿名函数中删除参数，该函数将在主体中可用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1710504|++++myButton.onclick+=+function()+{+alert(myMessage);+};|code-block|syntax|javascript|1710505|有关更多信息，请搜索“javascript闭包”|1710506|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|$]]

<p>By removing the parameter from the anonymous function will be available in the body.</p>

<pre><code>    myButton.onclick = function() { alert(myMessage); };
</code></pre>

<p>For more info search for 'javascript closures'</p>


blocks|key|1495519|text|您所做的不起作用，因为您正在将一个事件绑定到一个函数。因此，它是定义当事件被引发时将被调用的参数的事件(即JavaScript不知道你绑定到onclick的函数中的参数，所以不能向它传递任何东西)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495520|但是，您可以这样做：|1495521|<input+type="button"+value="Click+me"+id="myButton"/>

<script+type="text/javascript">

++++var+myButton+=+document.getElementById("myButton");

++++var+myMessage+=+"it's+working";

++++var+myDelegate+=+function(message)+{
++++++++alert(message);
++++}

++++myButton.onclick+=+function()+{+
++++++++myDelegate(myMessage);
++++};

</script>|code-block|syntax|javascript|1495522|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

<p>What you've done doesn't work because you're binding an event to a function.  As such, it's the event which defines the parameters that will be called when the event is raised (i.e. JavaScript doesn't know about your parameter in the function you've bound to onclick so can't pass anything into it). </p>

<p>You could do this however:</p>

<pre><code>&lt;input type="button" value="Click me" id="myButton"/&gt;

&lt;script type="text/javascript"&gt;

    var myButton = document.getElementById("myButton");

    var myMessage = "it's working";

    var myDelegate = function(message) {
        alert(message);
    }

    myButton.onclick = function() { 
        myDelegate(myMessage);
    };

&lt;/script&gt;
</code></pre>


blocks|key|1495570|text|您所做的是创建了一个新的匿名函数，该函数接受单个参数，然后将该参数分配给函数中的局部变量myMessage。由于实际上没有传递任何参数，并且没有传递值的参数变成了null，所以您的函数只是执行alert(null)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495571|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|$]]

<p>What you have done is created a new anonymous function that takes a single parameter which then gets assigned to the local variable myMessage inside the function. Since no arguments are actually passed, and arguments which aren't passed a value become null, your function just does alert(null).</p>


blocks|key|1710682|text|如果你这样写的话|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1710683|myButton.onclick+=+function()+{+alert(myMessage);+};|code-block|syntax|javascript|1710684|它会起作用，但我不知道这是否能回答你的问题。|1710685|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|$]]

<p>If you write it like</p>

<pre><code>myButton.onclick = function() { alert(myMessage); };
</code></pre>

<p>It will work, but I don't know if that answers your questions.</p>


blocks|key|1495629|text|示例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495630|<input+type="button"+value="Click+me"+id="myButton">
<script>
++++var+myButton+=+document.getElementById("myButton");
++++var+test+=+"zipzambam";
++++myButton.onclick+=+function(eventObject)+{
++++++++if+(!eventObject)+{
++++++++++++eventObject+=+window.event;
++++++++}
++++++++if+(!eventObject.target)+{
++++++++++++eventObject.target+=+eventObject.srcElement;
++++++++}
++++++++alert(eventObject.target);
++++++++alert(test);
++++};
++++(function(myMessage)+{
++++++++alert(myMessage);
++++})("Hello");
</script>|code-block|syntax|javascript|1495631|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|$]]

<p>Example:</p>

<pre><code>&lt;input type="button" value="Click me" id="myButton"&gt;
&lt;script&gt;
    var myButton = document.getElementById("myButton");
    var test = "zipzambam";
    myButton.onclick = function(eventObject) {
        if (!eventObject) {
            eventObject = window.event;
        }
        if (!eventObject.target) {
            eventObject.target = eventObject.srcElement;
        }
        alert(eventObject.target);
        alert(test);
    };
    (function(myMessage) {
        alert(myMessage);
    })("Hello");
&lt;/script&gt;
</code></pre>


blocks|key|1710718|text|代表们：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1710719|function+displayMessage(message,+f)
{
++++f(message);+//+execute+function+"f"+with+variable+"message"
}

function+alerter(message)
{
++++alert(message);
}

function+writer(message)
{
++++document.write(message);
}|code-block|syntax|javascript|1710720|运行displayMessage函数：|1710721|function+runDelegate()
{
++++displayMessage("Hello+World!",+alerter);+//+alert+message

++++displayMessage("Hello+World!",+writer);+//+write+message+to+DOM
}|1710722|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|$]]

<p>The delegates:</p>

<pre><code>function displayMessage(message, f)
{
    f(message); // execute function "f" with variable "message"
}

function alerter(message)
{
    alert(message);
}

function writer(message)
{
    document.write(message);
}
</code></pre>

<p>Running the displayMessage function:</p>

<pre><code>function runDelegate()
{
    displayMessage("Hello World!", alerter); // alert message

    displayMessage("Hello World!", writer); // write message to DOM
}
</code></pre>


blocks|key|1495691|text|事件处理程序需要一个参数，该参数是触发的事件。您恰好将其重命名为'myMessage‘，因此您警告的是事件对象而不是您的消息。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495692|闭包可以让您引用在函数外部定义的变量，但是，如果您使用的是Jquery，则可能需要查看其特定于事件的API，例如|1495693|http://docs.jquery.com/Events/bind#typedatafn|offset|length|1495694|它有一个用于传递您自己的数据的选项。|1495695|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|19|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|S|8|@]|9|@$F|T|G|U|1|V]]|A|$]]|$1|H|3|I|5|6|7|W|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|X|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|E]]]]

<p>Event handlers expect one parameter which is the event that was fired. You happen to be renaming that to 'myMessage' and therefore you are alerting the event object rather than your message.</p>

<p>A closure can allow you to reference the variable you have defined outside the function however if you are using Jquery you may want to look at its event specific API e.g.</p>

<p><a href="http://docs.jquery.com/Events/bind#typedatafn" rel="noreferrer">http://docs.jquery.com/Events/bind#typedatafn</a></p>

<p>This has an option for passing in your own data.</p>


blocks|key|1495727|text|下面是使用闭包解决您提到的问题的一种方法。它还考虑了这样一个事实，即可以在不影响绑定的情况下随时间改变消息。而且它使用了jQuery以使其简洁。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1495728|var+msg+=+(function(message){
++var+_message+=+message;
++return+{
++++say:function(){alert(_message)},
++++change:function(message){_message+=+message}
++};
})("My+Message");
$("#myButton").click(msg.say);|code-block|syntax|javascript|1495729|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|$]]

<p>The following is a method for using closures to address the issue to which you refer. It also takes into account the fact that may which to change the message over time without affecting the binding. And it uses jQuery to be succinct.</p>

<pre><code>var msg = (function(message){
  var _message = message;
  return {
    say:function(){alert(_message)},
    change:function(message){_message = message}
  };
})("My Message");
$("#myButton").click(msg.say);
</code></pre>


<p>I'm trying to figure out how to pass arguments to an anonymous function in JavaScript.</p>

<p>Check out this sample code and I think you will see what I mean:</p>

<pre><code>&lt;input type="button" value="Click me" id="myButton" /&gt;

&lt;script type="text/javascript"&gt;
    var myButton = document.getElementById("myButton");
    var myMessage = "it's working";
    myButton.onclick = function(myMessage) { alert(myMessage); };
&lt;/script&gt;
</code></pre>

<p>When clicking the button the message: <code>it's working</code> should appear.  However the <code>myMessage</code> variable inside the anonymous function is null.</p>

<p>jQuery uses a lot of anonymous functions, what is the best way to pass that argument?</p>


How can I pass arguments to anonymous functions in JavaScript?

jQuery

我正在尝试弄清楚如何在JavaScript中将参数传递给匿名函数。看看这段示例代码，我想你会明白我的意思：<input type="button" value="Click me" id="myButton" /><script type="text/javascript">    var myButton = doc...

问如何将参数传递给JavaScript中的匿名函数？
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