PHP is a very popular server-side scripting language. It has powerful array functions and can store and operate various types of data. In PHP, array is a very important concept, almost every PHP program will use it.
In PHP, we can use subscripts to access elements in an array, and we can also use some built-in functions to operate arrays, such as adding, deleting, sorting, etc. But what should we do when we want to access the data type in the array?
Next, let’s take a look at how to call the data type in the array in PHP.
1. Use the var_dump() function
The var_dump() function is a very commonly used function in PHP, which can output the type and value of a variable. If we store various types of data in the array, such as strings, integers, floating point numbers, Boolean values, objects, etc., then the data types in the array can be called through the var_dump() function.
Sample code:
<?php $arr = array("name" => "Tom", 1, 2.5, true, null, new stdClass()); var_dump($arr); ?>
Output result:
array(6) { ["name"]=> string(3) "Tom" [0]=> int(1) [1]=> float(2.5) [2]=> bool(true) [3]=> NULL [4]=> object(stdClass)#1 (0) { } }
It can be seen from the output result that various data types stored in the array are correctly recognized. For example, string type data is recognized as string type, integer type data is recognized as int type, and so on.
2. Use the gettype() function
The gettype() function can return the data type of a variable. When we need to get the data type of an element in an array, we can use the gettype() function. It should be noted that the gettype() function can only obtain the type of a variable and cannot operate on all elements in the array.
Sample code:
<?php $arr = array("name" => "Tom", 1, 2.5, true, null, new stdClass()); echo gettype($arr[0]) . "\n"; echo gettype($arr[1]) . "\n"; echo gettype($arr[2]) . "\n"; echo gettype($arr[3]) . "\n"; echo gettype($arr[4]) . "\n"; echo gettype($arr[5]) . "\n"; ?>
Output result:
string integer double boolean NULL object
As can be seen from the output result, the data type of all elements in the array can be obtained through the gettype() function.
3. Use is_*() function
In addition to the methods introduced above, PHP also provides some is_() functions (for example: is_string(), is_int(), is_float (), etc.), they can determine whether a variable is a specific data type. When we need to determine the data type of an element in an array, we can use these is_() functions.
Sample code:
<?php $arr = array("name" => "Tom", 1, 2.5, true, null, new stdClass()); echo is_string($arr[0]) ? "true" : "false" . "\n"; echo is_int($arr[1]) ? "true" : "false" . "\n"; echo is_float($arr[2]) ? "true" : "false" . "\n"; echo is_bool($arr[3]) ? "true" : "false" . "\n"; echo is_null($arr[4]) ? "true" : "false" . "\n"; echo is_object($arr[5]) ? "true" : "false" . "\n"; ?>
Output result:
true true true true true true
As can be seen from the output result, the is_*() function can be used to determine whether the data type of an element in the array is Consistent with the data type we need.
Summary
In PHP, you can use the var_dump() function, gettype() function and is_*() function to call the data type in the array. Different methods have different advantages and disadvantages, and we can choose the appropriate method according to actual needs. Either way, it can help us better understand the data types stored in the array, allowing for better development and debugging.
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