php - PHP是否具有结构，typedef和/或枚举，如果没有，则最佳的实现是什么？

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PHP and Enumerations

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7年前关闭。




NOTICE!: This question is not a duplicate: I have provided below an alternative and highly useful enumeration method that accomplishes the desired effect - 11/13/2013

PHP中是否有 typedef关键字，这样我可以执行以下操作:

typedef struct {

} aStructure;

要么

typedef enum {
  aType1,
  aType2,
} aType;

编辑

我最终在下面回答了我自己的问题。我创建了一个自定义的 enum函数，该函数可以完全实现我所要求的功能，但没有类型定义。

最佳答案

实际上，我为PHP创建了自己的一种枚举，它可以很好地满足我的需要。没有typedef，但它的好:D

函数枚举($ array，$ asBitwise = false)


/*
* I formed another version that includes typedefs
* but seeing how this hacky is not viewed as compliant
* with programming standards I won't post it unless someone
* wishes to request. I use this a lot to save me the hassle of manually
* defining bitwise constants, but if you feel it is too pointless
* for you I can understand. Not trying to reinvent the wheel here
*
*/
function enum(array $array, bool $asBitwise = false) {

if(!is_array($array) || count($array) < 1) return false; // Error incorrect type

$n = 0; // Counter variable
foreach($array as $i) {
if(!define($i, $n == 0 ? 0 : ($asBitwise ? 1 << ($n - 1) : $n))) return false;
++$n;
}
return true; // Successfully defined all variables

}


用法(示例):


enum([
'BrowserTypeUnknown', // 0
'BrowserTypeIE', // 1
'BrowserTypeNetscape', // 2
'BrowserTypeOpera', // 3
'BrowserTypeSafari', // 4
'BrowserTypeFirefox', // 5
'BrowserTypeChrome', // 6
]); // BrowserType as an Increment

$browser_type = BrowserTypeChrome;

if($browser_type == BrowserTypeOpera) {
// Make Opera Adjustments (will not execute)
} else
if($browser_type == BrowserTypeChrome) {
// Make Chrome Adjustments (will execute)
}

enum([
'SearchTypeUnknown', // 0
'SearchTypeMostRecent', // 1 << 0
'SearchTypePastWeek', // 1 << 1
'SearchTypePastMonth', // 1 << 2
'SearchTypeUnanswered', // 1 << 3
'SearchTypeMostViews', // 1 << 4
'SearchTypeMostActive', // 1 << 5
], true); // SearchType as BitWise

$search_type = SearchTypeMostRecent | SearchTypeMostActive;

if($search_type & SearchTypeMostRecent) {
// Search most recent files (will execute)
}
if($search_type & SearchTypePastWeek) {
// Search files from the past will (will not execute)
}

if($search_type & SearchTypeMostActive) {
// Search most active files AS WELL (will execute as well)
}



关于php - PHP是否具有结构，typedef和/或枚举，如果没有，则最佳的实现是什么？ ，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/3836385/

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Answer 1

实际上，我为PHP创建了自己的一种枚举，它可以很好地满足我的需要。没有typedef，但它的好:D

函数枚举($ array，$ asBitwise = false)


/*
* I formed another version that includes typedefs
* but seeing how this hacky is not viewed as compliant
* with programming standards I won't post it unless someone
* wishes to request. I use this a lot to save me the hassle of manually
* defining bitwise constants, but if you feel it is too pointless
* for you I can understand. Not trying to reinvent the wheel here
*
*/
function enum(array $array, bool $asBitwise = false) {

if(!is_array($array) || count($array) < 1) return false; // Error incorrect type

$n = 0; // Counter variable
foreach($array as $i) {
if(!define($i, $n == 0 ? 0 : ($asBitwise ? 1 << ($n - 1) : $n))) return false;
++$n;
}
return true; // Successfully defined all variables

}


用法(示例):


enum([
'BrowserTypeUnknown', // 0
'BrowserTypeIE', // 1
'BrowserTypeNetscape', // 2
'BrowserTypeOpera', // 3
'BrowserTypeSafari', // 4
'BrowserTypeFirefox', // 5
'BrowserTypeChrome', // 6
]); // BrowserType as an Increment

$browser_type = BrowserTypeChrome;

if($browser_type == BrowserTypeOpera) {
// Make Opera Adjustments (will not execute)
} else
if($browser_type == BrowserTypeChrome) {
// Make Chrome Adjustments (will execute)
}

enum([
'SearchTypeUnknown', // 0
'SearchTypeMostRecent', // 1 << 0
'SearchTypePastWeek', // 1 << 1
'SearchTypePastMonth', // 1 << 2
'SearchTypeUnanswered', // 1 << 3
'SearchTypeMostViews', // 1 << 4
'SearchTypeMostActive', // 1 << 5
], true); // SearchType as BitWise

$search_type = SearchTypeMostRecent | SearchTypeMostActive;

if($search_type & SearchTypeMostRecent) {
// Search most recent files (will execute)
}
if($search_type & SearchTypePastWeek) {
// Search files from the past will (will not execute)
}

if($search_type & SearchTypeMostActive) {
// Search most active files AS WELL (will execute as well)
}