blocks|key|966490|text|你说得对，这在任何情况下都是不可能的，因为只有值被传递到函数中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|966491|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>You're right, this is very much impossible in any sane way, since only the value gets passed into the function.</p>


blocks|key|1181027|text|多亏了ES6，这在某种程度上已经成为可能：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1181028|​|1181029|function+getVariableName(unknownVariableInAHash){
++return+Object.keys(unknownVariableInAHash)[0]
}

const+foo+=+42
const+bar+=+'baz'
console.log(getVariableName({foo}))+//returns+string+"foo"
console.log(getVariableName({bar}))+//returns+string+"bar"|code-block|syntax|javascript|1181030|1181031|唯一(小)的问题是你必须在{}之间包装你的未知变量，这没什么大不了的。|offset|length|style|CODE|1181032|entityMap^0|0|0|0|0|D|2|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|T|8|@]|9|@]|A|$G|H]]|$1|I|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|V|8|@$L|W|M|X|N|O]]|9|@]|A|$]]|$1|P|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|Q|$]]

<p>This is now somehow possible thanks to ES6:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>function getVariableName(unknownVariableInAHash){
  return Object.keys(unknownVariableInAHash)[0]
}

const foo = 42
const bar = 'baz'
console.log(getVariableName({foo})) //returns string "foo"
console.log(getVariableName({bar})) //returns string "bar"</code></pre>
</div>
</div>
</p>

<p>The only (small) catch is that you have to wrap your unknown variable between <code>{}</code>, which is no big deal.</p>


blocks|key|966645|text|所有的全局变量都是全局对象(this或window)的属性，不是吗？因此，当我想要找出变量的名称时，我创建了以下函数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|966646|var+getName+=+function(variable)+{
++for+(var+prop+in+window)+{
++++if+(variable+===+window[prop])+{
++++++return+prop;
++++}
++}
}
var+helloWorld+=+"Hello+World!";
console.log(getName(helloWorld));+//+"helloWorld"|code-block|syntax|javascript|966647|有时不起作用，例如，如果创建的两个字符串没有使用new运算符，并且具有相同的值。|966648|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>Well, all the global variables are properties of global object (this or window), aren't they?
So when I wanted to find out the name of my variables, I made following function:</p>

<pre><code>var getName = function(variable) {
  for (var prop in window) {
    if (variable === window[prop]) {
      return prop;
    }
  }
}
var helloWorld = "Hello World!";
console.log(getName(helloWorld)); // "helloWorld"
</code></pre>

<p>Sometimes doesn't work, for example, if 2 strings are created without new operator and have the same value.</p>


blocks|key|1181106|text|正如你想要调试的(show+name+of+var和value+of+var)，我也一直在寻找它，只是想分享我的发现。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1181107|这不是通过从var检索var的名称，而是通过相反的方式:从var的名称(以字符串形式)检索var的值。|1181108|可以不使用eval，只需非常简单的代码，只要将var传入函数并用引号括起来，并全局声明该变量：|1181109|foo+=+'bar';

debug('foo');+

function+debug(Variable)+{+
+var+Value+=+this[Variable];+//+in+that+occurrence,+it+is+equivalent+to
+//+this['foo']+which+is+the+syntax+to+call+the+global+variable+foo
+console.log(Variable+%2B+"+is+"+%2B+Value);++//+print+"foo+is+bar"
}|code-block|syntax|javascript|1181110|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<p>As you want debugging (show name of var and value of var),
I've been looking for it too, and just want to share my finding.</p>

<p>It is not by retrieving the name of the var from the var but the other way around : retrieve the value of the var from the name (as string) of the var.</p>

<p>It is possible to do it without eval, and with very simple code, at the condition you pass your var into the function with quotes around it, and you declare the variable globally :</p>

<pre><code>foo = 'bar';

debug('foo'); 

function debug(Variable) { 
 var Value = this[Variable]; // in that occurrence, it is equivalent to
 // this['foo'] which is the syntax to call the global variable foo
 console.log(Variable + " is " + Value);  // print "foo is bar"
}
</code></pre>


blocks|key|966554|text|全局w/string方法|type|unstyled|depth|inlineStyleRanges|entityRanges|data|966555|下面是一种技术，您可以使用它来保存变量的名称和值。|966556|​|966557|//+Set+up+a+global+variable+called+g
var+g+=+{};
//+All+other+variables+should+be+defined+as+properties+of+this+global+object
g.foo+=+'hello';
g.bar+=+'world';

//+Setup+function
function+doStuff(str)+{
++if+(str+in+g)+{
++++var+name+=+str;
++++var+value+=+g[str];
++++//+Do+stuff+with+the+variable+name+and+the+variable+value+here
++++//+For+this+example,+simply+print+to+console
++++console.log(name,+value);
++}+else+{
++++console.error('Oh+snap!+That+variable+does+not+exist!');
++}
}

//+Call+the+function
doStuff('foo');+//+log:+foo+hello
doStuff('bar');+//+log:+bar+world
doStuff('fakeVariable');+//+error:+Oh+snap!+That+variable+does+not+exist!|code-block|syntax|javascript|966558|966559|这有效地创建了一个将变量名称映射到它们的值的字典。如果不重构每个变量，这可能不适用于您现有的代码。但是使用这种风格，您可以实现对这类问题的解决方案。|966560|ES6对象方法|966561|在ES6/ES2015中，你可以使用名称和值initialize一个对象，这几乎可以实现你想要做的事情。|offset|length|966562|966563|function+getVariableName(unknownVariable)+{
++return+Object.keys(unknownVariable)[0];
}

var+foo+=+'hello';
var+output+=+getVariableName({+foo+});+//+Note+the+curly+brackets
console.log(output);|966564|966565|这是因为您创建了一个新对象，其键为foo，值与变量foo相同，在本例中为hello。然后，我们的helper方法将第一个键作为字符串获取。|style|CODE|966566|功劳归功于this+tweet。|966567|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer#New_notations_in_ECMAScript_2015|1|https://twitter.com/DaniStefanovic/status/1011923716085821440^0|0|0|0|0|0|0|0|M|A|0|0|0|0|0|H|3|10|5|0|5|A|1|0^^$0|@$1|2|3|4|5|6|7|1D|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1E|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|1F|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|1G|8|@]|9|@]|A|$I|J]]|$1|K|3|E|5|6|7|1H|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|1I|8|@]|9|@]|A|$]]|$1|N|3|O|5|6|7|1J|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|1K|8|@]|9|@$R|1L|S|1M|1|1N]]|A|$]]|$1|T|3|E|5|6|7|1O|8|@]|9|@]|A|$]]|$1|U|3|V|5|H|7|1P|8|@]|9|@]|A|$I|J]]|$1|W|3|E|5|6|7|1Q|8|@]|9|@]|A|$]]|$1|X|3|Y|5|6|7|1R|8|@$R|1S|S|1T|Z|10]|$R|1U|S|1V|Z|10]]|9|@]|A|$]]|$1|11|3|12|5|6|7|1W|8|@]|9|@$R|1X|S|1Y|1|1Z]]|A|$]]|$1|13|3|-4|5|6|7|20|8|@]|9|@]|A|$]]]|14|$15|$5|16|17|18|A|$19|1A]]|1B|$5|16|17|18|A|$19|1C]]]]

<h2>Global w/string method</h2>

<p>Here is a technique that you can use to keep the name and the value of the variable.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>// Set up a global variable called g
var g = {};
// All other variables should be defined as properties of this global object
g.foo = 'hello';
g.bar = 'world';

// Setup function
function doStuff(str) {
  if (str in g) {
    var name = str;
    var value = g[str];
    // Do stuff with the variable name and the variable value here
    // For this example, simply print to console
    console.log(name, value);
  } else {
    console.error('Oh snap! That variable does not exist!');
  }
}

// Call the function
doStuff('foo'); // log: foo hello
doStuff('bar'); // log: bar world
doStuff('fakeVariable'); // error: Oh snap! That variable does not exist!</code></pre>
</div>
</div>
</p>

<p>This is effectively creating a dictionary that maps variable names to their value. This probably won't work for your existing code without refactoring every variable. But using this style, you can achieve a solution for this type of problem.</p>

<h2>ES6 object method</h2>

<p>In ES6/ES2015, you are able to <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer#New_notations_in_ECMAScript_2015" rel="nofollow noreferrer">initialize</a> an object with name and value which can almost achieve what you are trying to do.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>function getVariableName(unknownVariable) {
  return Object.keys(unknownVariable)[0];
}

var foo = 'hello';
var output = getVariableName({ foo }); // Note the curly brackets
console.log(output);</code></pre>
</div>
</div>
</p>

<p>This works because you created a new object with key <code>foo</code> and value the same as the variable foo, in this case <code>hello</code>. Then our helper method gets the first key as a string.</p>

<p>Credit goes to <a href="https://twitter.com/DaniStefanovic/status/1011923716085821440" rel="nofollow noreferrer">this tweet</a>.</p>


blocks|key|966712|text|将一组唯一变量转换为一个JSON对象，我为该对象编写了以下函数|type|unstyled|depth|inlineStyleRanges|entityRanges|data|966713|function+makeJSON(){+//Pass+the+variable+names+as+string+parameters+[not+by+reference]
ret={};
for(i=0;+i<arguments.length;+i%2B%2B){
++++eval("ret."%2Barguments[i]%2B"="%2Barguments[i]);
}
return+ret;
}|code-block|syntax|javascript|966714|示例：|966715|a=b=c=3;
console.log(makeJSON('a','b','c'));|966716|也许这就是查询的原因|966717|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

<p>Converting a set of unique variable into one JSON object for which I wrote this function</p>

<pre><code>function makeJSON(){ //Pass the variable names as string parameters [not by reference]
ret={};
for(i=0; i&lt;arguments.length; i++){
    eval("ret."+arguments[i]+"="+arguments[i]);
}
return ret;
}
</code></pre>

<p>Example:</p>

<pre><code>a=b=c=3;
console.log(makeJSON('a','b','c'));
</code></pre>

<p>Perhaps this is the reason for this query</p>


blocks|key|966855|text|我想你可以用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|966856|getVariableName({foo});|code-block|syntax|javascript|966857|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>I think you can use</p>
<pre><code>getVariableName({foo});
</code></pre>


<p>I've got a feeling this might not be possible, but I would like to determine the original variable name of a variable which has been passed to a function in javascript. I don't know how to explain it any better than that, so see if this example makes sense.</p>

<pre><code>function getVariableName(unknownVariable){
  return unknownVariable.originalName;
}

getVariableName(foo); //returns string "foo";
getVariableName(bar); //returns string "bar";
</code></pre>

<p>This is for a jquery plugin i'm working on, and i would like to be able to display the name of the variable which is passed to a "debug" function.</p>


Determine original name of variable after its passed to a function

JSON

我有一种感觉，这可能是不可能的，但我想确定在javascript中传递给函数的变量的原始变量名。我不知道如何更好地解释它，所以看看这个例子是否有意义。function getVariableName(unknownVariable){  return unknownVariable.originalName;}getVariableName(foo); //returns string "foo"

问将变量传递给函数后确定变量的原始名称
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