blocks|key|55107|text|这不是变量，这是Array。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|55108|数组名称key+=+'value‘|55109|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|$]]

This is not a variable this is Array.

Array name [key] = 'value'

blocks|key|55129|text|这是在数组中定义键/值对。$config是一个数组，而'salt‘是该数组中的一个键。查看这里的文档：http://php.net/manual/en/language.types.array.php|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|55130|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/language.types.array.php^0|D|7|1F|1D|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]]|D|@$9|Q|A|R|1|S]]|E|$]]|$1|F|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

This is defining a key/value pair in an array. <code>$config</code> is an array, and 'salt' is one key in that array. Check out the docs here: <a href="http://php.net/manual/en/language.types.array.php" rel="nofollow">http://php.net/manual/en/language.types.array.php</a>

blocks|key|2658443|text|这是一个数组。变量是类型数组的名称(引用)+'$config‘。索引是'salt‘，值是'x2x3x5，这里是文档|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2658444|PHP数组文档|offset|length|2658445|entityMap|0|LINK|mutability|MUTABLE|url|http://us3.php.net/manual/en/language.types.array.php^0|0|0|7|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

This is an array . The variable is, of the type array, with the name (reference) '$config'. the index is 'salt' the value is 'x2x3x5
Here are the docs 

<a href="http://us3.php.net/manual/en/language.types.array.php" rel="nofollow">PHP Array Docs</a>

blocks|key|2658481|text|在线文档是一个很好的开端：可变范围|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2658482|但这里有一些澄清：|2658483|所有内容都在脚本的全局范围内。|2658484|$salt+=+'x2x3x5';
echo+$GLOBALS['salt'];+//+outputs+'x2x3x5'|code-block|syntax|javascript|2658485|直到你把它变成一个函数|2658486|$salt+=+'x2x3x5';
function+something()+{
++++$salt+=+'123';
++++return+$salt;
}
echo+something();+//+output+'123'
echo+$salt;+//+output+'x2x3x5'|2658487|如果将其封装在类属性中，则相同。|2658488|class+something()+{
++++public+static+$salt+=+'123';
}

$salt+=+'x2x3x5';
echo+something::$salt;+//+output+'123'
echo+$salt;+//+output+'x2x3x5'|2658489|最后，$config['salt']+=+'x2x3x5';使$config成为一个由键索引的值数组。此变量存在于已定义的作用域中(如果在全局作用域中，或在函数/类/方法中，则为全局变量)。|style|CODE|2658490|$config['salt']+=+'1234';
$config['pepper']+=+'abcde';
echo+$config['salt'];+//+output+1234
echo+$config['pepper'];+//+output'abcde'|2658491|entityMap|0|LINK|mutability|MUTABLE|url|http://www.php.net/manual/en/language.variables.scope.php^0|D|4|0|0|0|0|0|0|0|0|0|3|R|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@$A|19|B|1A|1|1B]]|C|$]]|$1|D|3|E|5|6|7|1C|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|1D|8|@]|9|@]|C|$]]|$1|H|3|I|5|J|7|1E|8|@]|9|@]|C|$K|L]]|$1|M|3|N|5|6|7|1F|8|@]|9|@]|C|$]]|$1|O|3|P|5|J|7|1G|8|@]|9|@]|C|$K|L]]|$1|Q|3|R|5|6|7|1H|8|@]|9|@]|C|$]]|$1|S|3|T|5|J|7|1I|8|@]|9|@]|C|$K|L]]|$1|U|3|V|5|6|7|1J|8|@$A|1K|B|1L|W|X]]|9|@]|C|$]]|$1|Y|3|Z|5|J|7|1M|8|@]|9|@]|C|$K|L]]|$1|10|3|-4|5|6|7|1N|8|@]|9|@]|C|$]]]|11|$12|$5|13|14|15|C|$16|17]]]]

The online docs are a good start: <a href="http://www.php.net/manual/en/language.variables.scope.php" rel="nofollow">Variable Scope</a>

But here's some clarification:

Everything is in the global scope for a script.

<pre><code>$salt = 'x2x3x5';
echo $GLOBALS['salt']; // outputs 'x2x3x5'
</code></pre>

Until you put it into a function

<pre><code>$salt = 'x2x3x5';
function something() {
 $salt = '123';
 return $salt;
}
echo something(); // output '123'
echo $salt; // output 'x2x3x5'
</code></pre>

Same if you wrap it up in a class property.

<pre><code>class something() {
 public static $salt = '123';
}

$salt = 'x2x3x5';
echo something::$salt; // output '123'
echo $salt; // output 'x2x3x5'
</code></pre>

Finally <code>$config['salt'] = 'x2x3x5';</code> makes $config an array of values indexed by keys. This variable exists in the scope which is defined (so global if in the global scope, or within a function/class/method).

<pre><code>$config['salt'] = '1234';
$config['pepper'] = 'abcde';
echo $config['salt']; // output 1234
echo $config['pepper']; // output'abcde'
</code></pre>

blocks|key|55190|text|你有充分的理由在这种情况下感到困惑！PHP有一个非常常用的数据结构，称为数组。在您的示例中，$config是一个非常普通的数组。数组允许您通过更短、更容易键入的名称来寻址数据。通常，"data“被称为值，用于寻址它的较短的名称称为"key”。您可以在这里阅读更多关于数组的信息：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|55191|http://ca1.php.net/manual/en/language.types.array.php|55192|您可能会感到困惑，因为$GLOBALS是一个特殊的数组。$GLOBALS是特殊的，因为每当您声明一个普通变量时，它都会自动添加键，如您的示例：$salt+=+'x2x3x5';|55193|实际上，如果运行以下代码：|55194|$GLOBALS['salt']+=+'the+salt!';
echo+$salt;|code-block|syntax|javascript|55195|然后你就会回响“盐！”这是因为每当您向globals添加键/值对时，也会创建一个变量。相反的情况也是如此；如果运行以下代码：|55196|$salt+=+'the+salt!';
echo+$GLOBALS['salt'];|55197|然后你就会回响“盐！”这是因为在定义变量时，还需要在特殊的$GLOBALS数组中定义键/值对。|55198|希望这能给你一些洞察力！|55199|entityMap|0|LINK|mutability|MUTABLE|url^0|1A|7|0|0|1H|0|0|B|8|S|8|1Z|H|0|0|0|0|0|T|8|0|0^^$0|@$1|2|3|4|5|6|7|15|8|@$9|16|A|17|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|18|8|@]|D|@$9|19|A|1A|1|1B]]|E|$]]|$1|H|3|I|5|6|7|1C|8|@$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]|$9|1H|A|1I|B|C]]|D|@]|E|$]]|$1|J|3|K|5|6|7|1J|8|@]|D|@]|E|$]]|$1|L|3|M|5|N|7|1K|8|@]|D|@]|E|$O|P]]|$1|Q|3|R|5|6|7|1L|8|@]|D|@]|E|$]]|$1|S|3|T|5|N|7|1M|8|@]|D|@]|E|$O|P]]|$1|U|3|V|5|6|7|1N|8|@$9|1O|A|1P|B|C]]|D|@]|E|$]]|$1|W|3|X|5|6|7|1Q|8|@]|D|@]|E|$]]|$1|Y|3|-4|5|6|7|1R|8|@]|D|@]|E|$]]]|Z|$10|$5|11|12|13|E|$14|G]]]]

You have good reason to be confused in this case!
PHP has a very commonly used data structure called an array. <code>$config</code>, in your example, is a perfectly ordinary array. Arrays can allow you to address data by a shorter, easy to type name. Typically the "data" is called a value, and the shorter name you use to address it is called a "key". You can read more about arrays here:

<a href="http://ca1.php.net/manual/en/language.types.array.php" rel="nofollow">http://ca1.php.net/manual/en/language.types.array.php</a>

You are likely confused because <code>$GLOBALS</code> is a special array. <code>$GLOBALS</code> is special because it will automatically have keys added to it whenever you declare a normal variable, 
as in your example: <code>$salt = 'x2x3x5';</code>

In fact, if you run the following code:

<pre><code>$GLOBALS['salt'] = 'the salt!';
echo $salt;
</code></pre>

Then you will echo 'the salt!'. This is because whenever you add a key/value pair to globals, you are ALSO creating a variable. The opposite holds true too; If run this code:

<pre><code>$salt = 'the salt!';
echo $GLOBALS['salt'];
</code></pre>

then you will echo 'the salt!'. This is because when you define a variable, you ALSO define a key/value pair in the special <code>$GLOBALS</code> array.

Hope this gives you some insight!

blocks|key|55227|text|我认为您把数组与php的变量搞混了。在这里，$config是一个数组，它已经在您的当前文件中或者在您的php项目中的其他文件中定义。现在，它可能在另一个文件中，这让您感到困惑。检查当前文件(包含$config['salt']+=+'x2x3x5';的文件)中包含了哪些文件，并在随附的每个文件中查找$config数组变量。我希望您能找到将$config变量定义为数组的文件。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|55228|entityMap^0|M|7|2P|R|45|7|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

I think you are confusing array with php's variable.
Here <code>$config</code> is an array which has been defined in your current file or in some other file in your php project. Right now it may be in the other file which is making you confused. Check which files have been included in your current file (file that contains <code>$config['salt'] = 'x2x3x5';</code>) and look for a <code>$config</code> array variable in each file that comes along. I hope you'll find the file where $config variable has been defined as array.

According to my understanding PHP has three different variable scopes as:

<ol>
<li>local like <code>$salt = 'x2x3x5';</code> </li>
<li>GLOBAL like <code>$GLOBALS['salt'] = 'x2x3x5';</code> </li>
<li>static like <code>static $salt = 'x2x3x5';</code></li>
</ol>

But I saw on an online tutorial which the instructor declared and used a variable like below:

<pre><code>$config['salt'] = 'x2x3x5';
</code></pre>

Can you please let me know what kind of variable is this? and what is it's usage? Thanks

Issue on Declaring PHP Variable

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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根据我的理解，PHP有三个不同的变量范围如下：像$salt = 'x2x3x5';这样的局部像$GLOBALS['salt'] = 'x2x3x5';这样的全局静态类static $salt = 'x2x3x5';但是，我在一个在线教程上看到，教员声明并使用了一个变量，如下所示：$config['salt'] = 'x...

问关于声明PHP变量的问题
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