PHP array_merge merge and split two arrays_PHP tutorial-PHP Tutorial-php.cn

I was confused about the array_merge function and + operator of arrays, so I wrote a small program to compare them and found their differences. Especially the + operator, which means to append the right array unit (to remove duplicates) to the left array.

The code is as follows

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代码如下

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$arr1=array("a","b","c");
$arr2=array("c","d","e");

$myarray=array_merge($arr1,$arr2);
print_r($myarray);

$myarray=array_unique($myarray);

print_r($myarray);
?>

$arr1=array("a","b","c");
$arr2=array("c","d","e");

$myarray=array_merge($arr1,$arr2);
print_r($myarray);

$myarray=array_unique($myarray);

代码如下	复制代码
$array1=array(1, 2);//数组1 $array2=array(2, 3);//数组2 $array3=array_merge($array1, $array2);//合并数组; $array3=array_unique($array3);//移除数组中重复的值 ?>

print_r($myarray);
?> Example

The code is as follows	Copy code
$array1=array(1, 2);//array 1 $array2=array(2, 3);//Array 2 $array3=array_merge($array1, $array2);//Merge arrays; $array3=array_unique($array3);//Remove duplicate values in the array ?>

例子

代码如下

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代码如下

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结果如下：

第一种情况
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
    [6] => 7
    [7] => 8
    [8] => 9
)
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
)
Array
(
    [0] => 7
    [1] => 8
    [2] => 9
    [3] => 4
    [4] => 5
    [5] => 6
)

第二种情况
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
    [6] => a
    [7] => x
    [8] => y
)
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
)
Array
(
    [0] => a
    [1] => x
    [2] => y
    [3] => d
    [4] => e
    [5] => f
)

第三种情况
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
    [6] => a
    [7] => x
    [8] => y
)
Array
(
    [1] => a
    [2] => b
    [3] => c
    [4] => d
    [5] => e
    [6] => f
    [7] => x
    [8] => y
)
Array
(
    [1] => a
    [7] => x
    [8] => y
    [2] => b
    [3] => c
    [4] => d
    [5] => e
    [6] => f
)

echo "rn第一种情况rn";
$a=array(1,2,3,4,5,6);
$b=array(7,8,9);

$c=array_merge ($a,$b);
print_r($c);
$c=$a+$b;
print_r($c);
$c=$b+$a;
print_r($c);

echo "rn第二种情况rn";
$a=array('a','b','c','d','e','f');
$b=array('a','x','y');

$c=array_merge ($a,$b);
print_r($c);
$c=$a+$b;
print_r($c);
$c=$b+$a;
print_r($c);

echo "rn第三种情况rn";

$a=array(
1=>'a',
2=>'b',
3=>'c',
4=>'d',
5=>'e',
6=>'f');
$b=array(
1=>'a',
7=>'x',
8=>'y');

$c=array_merge ($a,$b);
print_r($c);
$c=$a+$b;
print_r($c);
$c=$b+$a;
print_r($c);
?> 结果如下：第一种情况
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
    [6] => 7
    [7] => 8
    [8] => 9
)
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
)
Array
(
    [0] => 7
    [1] => 8
    [2] => 9
    [3] => 4
    [4] => 5
    [5] => 6
)

第二种情况
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
    [6] => a
    [7] => x
    [8] => y
)
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
)
Array
(
    [0] => a
    [1] => x
    [2] => y
    [3] => d
    [4] => e
    [5] => f
)

第三种情况
Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
    [6] => a
    [7] => x
    [8] => y
)
Array
(
    [1] => a
    [2] => b
    [3] => c
    [4] => d
    [5] => e
    [6] => f
    [7] => x
    [8] => y
)
Array
(
    [1] => a
    [7] => x
    [8] => y
    [2] => b
    [3] => c
    [4] => d
    [5] => e
    [6] => f
)

Split array array_slice()
The array_slice() function will return a portion of the array, starting from the key offset and ending at offset+length. Its form:

Php code
1.array array_slice (array array, int offset[,int length])
array array_slice (array array, int offset[,int length])
When offset is a positive value, splitting will start at offset from the beginning of the array; if offset is negative, splitting will start at offset from the end of the array. If the optional length parameter is omitted, the split will start at offset and go to the last element of the array. If length is given and is positive, it ends at offset+length from the beginning of the array. Conversely, if length is given and is negative, it ends at count(input_array)-|length| from the beginning of the array. Consider an example:

Php code

The code is as follows

代码如下

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$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_slice($fruits, 3);
print_r($subset);

// output
// Array ( [0] => Pear [1] => Grape [2] => Lemon [3] => Watermelon )
?>

Copy code

代码如下

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$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_slice($fruits, 2, -2);
print_r($subset);

// output
// Array ( [0] => Orange [1] => Pear [2] => Grape )
?>

$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon"); $subset = array_slice($fruits, 3); print_r($subset); //output

// Array ( [0] => Pear [1] => Grape [2] => Lemon [3] => Watermelon )

Related labels：

array merge php function merge and right Split array Compare of operator

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