
array_column:以下摘自php手册
$records = array(array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
),
array(
'id' => 5342,
'first_name' => 'Jane',
'last_name' => 'Jones',
),
array(
'id' => 5623,
'first_name' => 'Peter',
'last_name' => 'Doe',
)
);
$first_names = array_column($records, 'first_name');
print_r($first_names);
>
以上例程会输出:
Array
(
[0] => John
[1] => Sally
[2] => Jane
[3] => Peter
)
介绍一下简单数组使用
一、数组定义:
数组的定义使用 array()方式定义,可以定义空数组:
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<php
$number = array(1,3,5,7,9);
//定义空数组
$result = array();
$color =array("red","blue","green");
//自定义键值
$language = (1=>"English",3=>"Chinese",5=>"Franch");
//定义二维数组
$two = array(
"color"=>array("red","blue"), //用逗号结尾
"week"=>array("Monday","Friday") //最后一句没有标点
);
>
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二、创建数组:
创建数组包含的函数有compact()、
1compact()函数——将一个或多个变量(包含数组)转换为数组:
array compact ( mixed $varname [, mixed $ ] )
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<PHP
$number = "1,3,5,7,9";
$string = "I'm PHPer";
$array = array("And","You");
$newArray = compact("number","string","array");
print_r ($newArray);
>
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compact()函数用于将两个或多个变量转换为数组,当然也包含数组变量。其参数是变量的名称而非带有$全名。
相反的函数是extract()作用顾名思义就是将数组转换为单个的字符串,键值作为其字符串名称,数组值作为字符串的值。
运行结果:
Array ( [number] => 1,3,5,7,9 [string] => I'm PHPer [array] => Array ( [0] => And [1] => You ) )
2array_combine()——将两个数组重组成一个数组,一个作键值一个做的值:
array array_combine ( array $keys , array $values )
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<PHP
$number = array("1","3","5","7","9");
$array = array("I","Am","A","PHP","er");
$newArray = array_combine($number,$array);
print_r ($newArray);
>
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array_combine函数不多说了,谁看了都明白
运行结果:
Array ( [1] => I [3] => Am [5] => A [7] => PHP [9] => er )
3range()函数——创建指定范围的数组:
不多说了,直接上实例——
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<PHP
$array1 = range(0,100,10);//0为起始值,100为结束值,10为步进值(默认步进值为1)
print_r($array1);
echo"<br />";
$array2 = range("A","Z");
print_r($array2);
echo "<br />";
$array3 = range("z","a");
print_r($array3);
>
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range()函数的默认步进值是1!
运行结果:
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Array ( [0] => 0 [1] => 10 [2] => 20 [3] => 30 [4] => 40 [5] => 50 [6] => 60 [7] => 70 [8] => 80 [9] => 90 [10] => 100 )
Array ( [0] => A [1] => B [2] => C [3] => D [4] => E [5] => F [6] => G [7] => H [8] => I [9] => J [10] => K [11] => L [12] => M [13] => N [14] => O [15] => P [16] => Q [17] => R [18] => S [19] => T [20] => U [21] => V [22] => W [23] => X [24] => Y [25] => Z )
Array ( [0] => z [1] => y [2] => x [3] => w [4] => v [5] => u [6] => t [7] => s [8] => r [9] => q [10] => p [11] => o [12] => n [13] => m [14] => l [15] => k [16] => j [17] => i [18] => h [19] => g [20] => f [21] => e [22] => d [23] => c [24] => b [25] => a )
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4array_fill()函数——填充数组函数:
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<PHP
$array = range(1,10);
$fillarray = range("a","d");
$arrayFilled = array_fill(0,5,$fillarray);//这里的$fillarray可以是字符串,如"test"
echo "<pre>";
print_r ($arrayFilled);
echo "</pre>";
$keys = array("string","2",9,"SDK","PK");
$array2 = array_fill_keys($keys,"testing");
echo "<pre>";
print_r ($array2);
echo "</pre>";
>
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运行结果:
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Array
(
[0] => Array
(
[0] => a
[1] => b
[2] => c
[3] => d
)
[1] => Array
(
[0] => a
[1] => b
[2] => c
[3] => d
)
[2] => Array
(
[0] => a
[1] => b
[2] => c
[3] => d
)
[3] => Array
(
[0] => a
[1] => b
[2] => c
[3] => d
)
[4] => Array
(
[0] => a
[1] => b
[2] => c
[3] => d
)
)
Array
(
[string] => testing
[2] => testing
[9] => testing
[SDK] => testing
[PK] => testing
)
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三、数组的遍历:
1foreach遍历:
foreach (array_expression as $value){}
foreach (array_expression as $key => $value){}
闲话少说,上实例:
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<PHP
$speed = array(50,120,180,240,380);
foreach($speed as $keys=>$values){
echo $keys"=>"$values"<br />";
}
>
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运行结果:
0=>50
1=>120
2=>180
3=>240
4=>380
2while循环遍历:
while循环遍历一般结合list函数,以下是实例
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<PHP
$staff = array(
array("姓名","性别","年龄"),
array("小张","男",24),
array("小王","女",25),
array("小李","男",23)
);
echo "<table border=2>";
while(list($keys,$value) = each($staff)){
list($name,$sex,$age) = $value;
echo "<tr><td>$name</td><td>$sex</td><td>$age</td></tr>";
}
echo "</table>";
>
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运行结果:
姓名 性别 年龄
小张 男 24
小王 女 25
小李 男 23
3for循环遍历:
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<PHP
$speed = range(0,220,20);
for($i =0;$i<count($speed);$i++) {
echo $speed[$i]" ";
}
>
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运行结果:
0 20 40 60 80 100 120 140 160 180 200 220
实例
创建名为 $cars 的索引数组,向它赋三个元素,然后打印包含数组值的文本:
<php
$cars=array("Volvo","BMW","Toyota");
echo "I like " $cars[0] ", " $cars[1] " and " $cars[2] "";
>
运行实例
定义和用法
array() 函数用于创建数组。
在 PHP 中,有三种类型的数组:
索引数组 - 带有数字索引的数组
关联数组 - 带有指定的键的数组
多维数组 - 包含一个或多个数组的数组
说明
array() 创建数组,带有键和值。如果在规定数组时省略了键,则生成一个整数键,这个 key 从 0 开始,然后以 1 进行递增。
要用 array() 创建一个关联数组,可使用 => 来分隔键和值。
要创建一个空数组,则不传递参数给 array():
以上就是关于PHP中取出二维数组或多维数组中每个数组的相同位置的元素组成一个新的数组全部的内容,包括:PHP中取出二维数组或多维数组中每个数组的相同位置的元素组成一个新的数组、如何学习PHP array、php中的array()函数如何使用等相关内容解答,如果想了解更多相关内容,可以关注我们,你们的支持是我们更新的动力!
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