blocks|key|1102798|text|var+thisline+=+new+Error().lineNumber|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102799|如果这在您使用的任何环境中都不起作用，您可以尝试：|1102800|var+stack+=+new+Error().stack|1102801|然后在堆栈中搜索行号。|1102802|entityMap^0|0|11|0|0|0|T|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Q|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|R|8|@$9|S|A|T|B|C]]|D|@]|E|$]]|$1|J|3|K|5|6|7|U|8|@]|D|@]|E|$]]|$1|L|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|M|$]]

<code>var thisline = new Error().lineNumber</code>

If that doesn't work in whatever environment you're using, you can try: 

<code>var stack = new Error().stack</code> 

Then hunt through the stack for the line number.

blocks|key|1317775|text|您可以尝试：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317776|window.onerror+=+handleError;
function+handleError(err,+url,+line){
++++alert(err+%2B+'\n+on+page:+'+%2B+url+%2B+'\n+on+line:+'+%2B+line);
}|code-block|syntax|javascript|1317777|然后在你想知道的地方抛出一个错误(不是很想知道，但如果你正在调试，它可能会对你有帮助。|1317778|注意：window.onerror不是在WebKit或Opera中定义/处理的(我上次检查的时候)|offset|length|style|CODE|1317779|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/WebKit|1|https://en.wikipedia.org/wiki/Opera_%2528web_browser%2529^0|0|0|0|3|E|K|6|0|R|5|1|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|11|8|@$K|12|L|13|M|N]]|9|@$K|14|L|15|1|16]|$K|17|L|18|1|19]]|A|$]]|$1|O|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]|W|$5|R|S|T|A|$U|X]]]]

You can try:

<pre><code>window.onerror = handleError;
function handleError(err, url, line){
 alert(err + '\n on page: ' + url + '\n on line: ' + line);
}
</code></pre>

Then throw an error where you want to know (not overly desired, but it might help you if you are debugging.

Note: <code>window.onerror</code> isn't defined/handled in <a href="https://en.wikipedia.org/wiki/WebKit" rel="nofollow noreferrer">WebKit</a> or <a href="https://en.wikipedia.org/wiki/Opera_%28web_browser%29" rel="nofollow noreferrer">Opera</a> (the last time I checked)

blocks|key|1102897|text|你可以尝试解析一个函数的源代码来寻找一些标记。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102898|这里有一个简单的例子(是的，它有一点混乱)。|1102899|function+foo()++
{+++++++
++++alert(line(1));
++++var+a;
++++var+b;++++++
++++alert(line(2));
}+++
foo();

function+line(mark)
{
++++var+token+=+'line\$'+%2B+mark+%2B+'\$';+++++++
++++var+m+=+line.caller.toString().match(
++++++++new+RegExp('(%5E(?!.*'+%2B+token+%2B+'))%7C('+%2B+token+%2B+')',+'gm'))+%7C%7C+[];
++++var+i+=+0;
++++for+(;+i+<+m.length;+i%2B%2B)+if+(m[i])+break;
++++return+i+%2B+1;
}|code-block|syntax|javascript|1102900|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|$]]

You can try to parse a source of a function to seek some marks. 
Here is a quick example (yes, it's messed a little).

<pre><code>function foo() 
{ 
 alert(line(1));
 var a;
 var b; 
 alert(line(2));
} 
foo();

function line(mark)
{
 var token = 'line\$' + mark + '\$'; 
 var m = line.caller.toString().match(
 new RegExp('(^(?!.*' + token + '))|(' + token + ')', 'gm')) || [];
 var i = 0;
 for (; i &lt; m.length; i++) if (m[i]) break;
 return i + 1;
}
</code></pre>

blocks|key|1317856|text|将以下代码片段注入您的代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317857|console.debug("line:",+/\(file:[\w\d/.-]%2B:([\d]%2B)/.exec(new+Error().stack)[1]);|code-block|syntax|javascript|1317858|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|$]]

Inject the following snippet to your code:

<pre><code>console.debug("line:", /\(file:[\w\d/.-]+:([\d]+)/.exec(new Error().stack)[1]);
</code></pre>

blocks|key|1102984|text|在不同浏览器和浏览器版本之间的可移植性更好(应该适用于火狐、Chrome和IE10%2B)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102985|function+ln()+{
++var+e+=+new+Error();
++if+(!e.stack)+try+{
++++//+IE+requires+the+Error+to+actually+be+throw+or+else+the+Error's+'stack'
++++//+property+is+undefined.
++++throw+e;
++}+catch+(e)+{
++++if+(!e.stack)+{
++++++return+0;+//+IE+<+10,+likely
++++}
++}
++var+stack+=+e.stack.toString().split(/\r\n%7C\n/);
++//+We+want+our+caller's+frame.+It's+index+into+%7Cstack%7C+depends+on+the
++//+browser+and+browser+version,+so+we+need+to+search+for+the+second+frame:
++var+frameRE+=+/:(\d%2B):(?:\d%2B)[%5E\d]*$/;
++do+{
++++var+frame+=+stack.shift();
++}+while+(!frameRE.exec(frame)+&&+stack.length);
++return+frameRE.exec(stack.shift())[1];
}|code-block|syntax|javascript|1102986|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|$]]

A bit more portable between different browsers and browser versions (should work in Firefox, Chrome and IE10+):

<pre><code>function ln() {
 var e = new Error();
 if (!e.stack) try {
 // IE requires the Error to actually be throw or else the Error's 'stack'
 // property is undefined.
 throw e;
 } catch (e) {
 if (!e.stack) {
 return 0; // IE &lt; 10, likely
 }
 }
 var stack = e.stack.toString().split(/\r\n|\n/);
 // We want our caller's frame. It's index into |stack| depends on the
 // browser and browser version, so we need to search for the second frame:
 var frameRE = /:(\d+):(?:\d+)[^\d]*$/;
 do {
 var frame = stack.shift();
 } while (!frameRE.exec(frame) &amp;&amp; stack.length);
 return frameRE.exec(stack.shift())[1];
}
</code></pre>

blocks|key|1317946|text|您可以使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317947|function+test(){
++++console.trace();
}

test();|code-block|syntax|javascript|1317948|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|$]]

You can use:

<pre><code>function test(){
 console.trace();
}

test();
</code></pre>

blocks|key|1318074|text|纯粹从Error.stack中无法获得行号，因为在Angular中，行号是编译代码的行号。但是可以获得错误是以哪种方法创建的信息。此代码片段中的类Logger将此信息添加到新的日志记录条目中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1318075|https://stackblitz.com/edit/angular-logger?file=src/app/Logger/logger.ts|offset|length|1318076|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|20|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@$D|O|E|P|1|Q]]|A|$]]|$1|F|3|-4|5|6|7|R|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|C]]]]

Purely one can't get the line number out of Error.stack, because in Angular the line number is the line number of the compiled code. But one can get the info in which method the error was created. The class Logger in this code snippet add this piece of information to a new logbook entry.

<a href="https://stackblitz.com/edit/angular-logger?file=src/app/Logger/logger.ts" rel="nofollow noreferrer">https://stackblitz.com/edit/angular-logger?file=src/app/Logger/logger.ts</a>

Does JavaScript have a mechanism for determining the line number of the currently executing statement (and if so, what is it)?

How can I determine the current line number in JavaScript?

JavaScript是否有机制来确定当前正在执行的语句的行号(如果有，是什么)？

问如何确定JavaScript中的当前行号？
EN

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