blocks|key|5454763|text|尝试添加第二组分组括号：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5454764|$result+=+(0+==+0)+?+'Option+0'+:+((1==2)+?+'Option+1'+:+'Option+2');|code-block|syntax|javascript|5454765|干杯|5454766|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|$]]

Try adding a second set of grouping parens:

<pre><code>$result = (0 == 0) ? 'Option 0' : ((1==2) ? 'Option 1' : 'Option 2');
</code></pre>

Cheers

blocks|key|5365144|text|您必须将第二个路径用引号括起来：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5365145|++$result+=+(0+==+0)?'Option+0':((1==2)?'Option+1':'Option+2');|code-block|syntax|javascript|5365146|顺便说一句:由于这种意外的行为，不推荐使用嵌套/堆叠三元。请参阅php文档http://php.net/manual/en/language.operators.comparison.php|offset|length|5365147|5365148|注意:建议您避免“堆叠”三元表达式。在一条语句中使用多个三元运算符时，PHP的行为并不明显：|blockquote|5365149|5365150|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/language.operators.comparison.php^0|0|0|11|1M|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Y|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Z|8|@]|9|@$I|10|J|11|1|12]]|A|$]]|$1|K|3|-4|5|6|7|13|8|@]|9|@]|A|$]]|$1|L|3|M|5|N|7|14|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|A|$]]|$1|P|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|Q|$R|$5|S|T|U|A|$V|W]]]]

You have to group the second path in quotes:

<pre><code> $result = (0 == 0)?'Option 0':((1==2)?'Option 1':'Option 2');
</code></pre>

BTW: Nesting / Stacking ternary is not recommended due to this unexpected behavior. See the php documentation <a href="http://php.net/manual/en/language.operators.comparison.php" rel="nofollow">http://php.net/manual/en/language.operators.comparison.php</a>

<blockquote>
 Note: It is recommended that you avoid "stacking" ternary expressions. PHP's behaviour when using more than one ternary operator within a single statement is non-obvious: 
</blockquote>

blocks|key|5365157|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5365158|$result+=+(0+==+0)?+'Option+0':((1==2)+?+'Option+1'+:+'Option+2');|code-block|syntax|javascript|5365159|输出：|5365160|Option+0|offset|length|style|CODE|5365161|entityMap^0|0|0|0|0|8|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]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Try this:

<pre><code>$result = (0 == 0)? 'Option 0':((1==2) ? 'Option 1' : 'Option 2');
</code></pre>

Output:

<code>Option 0</code>

blocks|key|5454823|text|这是因为它是右关联的(现在找不到源码)--首先计算右手边。因此，首先对这部分进行评估：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5454824|?+'Option+1'+:+'Option+2';|code-block|syntax|javascript|5454825|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|$]]

It's to do with it being right-associative (can't find source right now) - the right hand side is evaluated first. So, this part is evaluated first: 

<pre><code>? 'Option 1' : 'Option 2';
</code></pre>

blocks|key|3243295|text|您在这里遇到了和的问题。在您放置括号的地方，您的理解不足变得明显。让我们回顾一下：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3243296|$result+=+(0+==+0)+?+'Option+0'+:+(1+==+2)+?+'Option+1'+:+'Option+2';
++++++++++%5E++++++%5E++++++++++++++++%5E+++++%5E|code-block|syntax|javascript|3243297|我并不是说这很容易，但是正如这段代码已经显示的那样，您在这里放置了多余的圆括号。它们是不需要的，这通常是自己的代码不确定的标志。正确的变体应该是：|3243298|$result+=+0+==+0+?+'Option+0'+:+1+==+2+?+'Option+1'+:+'Option+2';|3243299|现在，这已经表明您不确定将括号放在哪里。了解了这一点，也包含了你问题的解决方案。将你的弱点转化为优势，只需先做第一次检查，然后再做第二次检查--但这一次要实际使用括号：|3243300|$result+=+0+==+0+?+'Option+0'+:+(1+==+2+?+'Option+1'+:+'Option+2');
++++++++++++++++++++++++++++++++%5E++++++++++++++++++++++++++++++++%5E|3243301|这将为您提供预期的结果，即括号控制优先级。|3243302|3243303|提示:您可以通过在编写以下语句时使用缩进来使更明显：|3243304|$result+=+
++++0+==+0+?+'Option+0'+
+++++++++++:+(1+==+2+?+'Option+1'+
+++++++++++++++++++++:+'Option+2')
;|3243305|(或类似的)只是为了让它在第一眼看起来更易读。正如它所显示的，这是一个复杂的决定。与复杂的事情一样，为它们编写代码时出现错误的情况也更多。这很正常。通过使用缩进来保持代码的可读性会有所帮助。另一种方法是降低复杂性。|3243306|$decide++=+2:
$results+=+array(
++++0+=>+'Option+0',+
++++1+=>+'Option+1',
);
$result++=+isset($results[$decide])+?+$results[$decide]+:+'Default+Option';|3243307|这里只需要一个决定，所以它就不那么复杂了。如果您有三种以上的可能性，则此示例更有意义，但即使对于三种可能性，这也可能是一种改进，因为在前面很明显存在默认情况。|3243308|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|13|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|14|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|15|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|16|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|17|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|18|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|19|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]|$1|R|3|S|5|6|7|1B|8|@]|9|@]|A|$]]|$1|T|3|U|5|D|7|1C|8|@]|9|@]|A|$E|F]]|$1|V|3|W|5|6|7|1D|8|@]|9|@]|A|$]]|$1|X|3|Y|5|D|7|1E|8|@]|9|@]|A|$E|F]]|$1|Z|3|10|5|6|7|1F|8|@]|9|@]|A|$]]|$1|11|3|-4|5|6|7|1G|8|@]|9|@]|A|$]]]|12|$]]

You have an issue with <a href="http://php.net/language.operators.precedence" rel="nofollow">Operator Precedence</a> and the <a href="http://php.net/language.operators.comparison#language.operators.comparison.ternary" rel="nofollow">Ternary Operator</a> here. Your lack of understanding becomes visible where you place the parenthesis. Let's review:

<pre><code>$result = (0 == 0) ? 'Option 0' : (1 == 2) ? 'Option 1' : 'Option 2';
 ^ ^ ^ ^
</code></pre>

I'm not saying it is easy, but as this code already shows, you have placed superfluous round brackets here. They are just not needed, this is often a sign of uncertainty with the own code. The correct variant would be:

<pre><code>$result = 0 == 0 ? 'Option 0' : 1 == 2 ? 'Option 1' : 'Option 2';
</code></pre>

Now, this already shows that you are uncertain about where to place the parentheses. Knowing about this, also contains the solution to your problem. Turn your weakness into a strength by just doing the first check first and the second, second - but this time making actual use of parenthesis:

<pre><code>$result = 0 == 0 ? 'Option 0' : (1 == 2 ? 'Option 1' : 'Option 2');
 ^ ^
</code></pre>

This will give you your expected result, the parenthesis control precedence now as intended.

<hr>

Tip: You can make the <a href="http://en.wikipedia.org/wiki/Decision_tree" rel="nofollow">decision tree</a> more visible by using indentation when you write such statements:

<pre><code>$result = 
 0 == 0 ? 'Option 0' 
 : (1 == 2 ? 'Option 1' 
 : 'Option 2')
;
</code></pre>

(or similar) Just to make this more readable at first glance. As it shows this is a complex decision. As with complex things, errors in writing code for them occur more often. That is normal. Keeping the code readable by using indentation can help. Another way is to reduce the complexity.

<pre><code>$decide = 2:
$results = array(
 0 =&gt; 'Option 0', 
 1 =&gt; 'Option 1',
);
$result = isset($results[$decide]) ? $results[$decide] : 'Default Option';
</code></pre>

Here only one decision is needed, so it is less complex. This example makes more sense if you have more than three possibilities but even for three possibilities this can already be an improvement because it is visible right ahead that there is a default case.

This outputs 'Option 1'. I have no idea what is wrong with it.

<pre><code>$result = (0 == 0) ? 'Option 0' : (1==2) ? 'Option 1' : 'Option 2';
</code></pre>

Thanks!

Nested ternery operators output wierd result

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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这将输出'Option 1‘。我不知道它出了什么问题。$result = (0 == 0) ? 'Option 0' : (1==2) ? 'Option 1' : 'Option 2';谢谢!

问嵌套的ternery运算符输出wierd结果
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问嵌套的ternery运算符输出wierd结果EN