PHP之数组学习 |
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本文标签：数组 今天学习了数组，可以说是PHP的数据应用中较重要的一种方式 。PHP的数组函数众多，下面是我学习的小结，借此记之，便于以后鉴之…… 一、数组定义： 数组的定义使用 array（）方式定义，可以定义空数组： 复制代码 代码如下: <?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 )； ?> 二、创建数组： 创建数组包含的函数有compact()、 1.compact()函数——将一个或多个变量（包含数组）转换为数组： array compact ( mixed $varname [, mixed $... ] ) 复制代码 代码如下: <?PHP $number = "1,3,5,7,9"; $string = "Im PHPer"; $array = array("And","You?"); $newArray = compact("number","string","array"); print_r ($newArray); ?> 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: 复制代码 代码如下: Array ( [number] => 1,3,5,7,9 [string] => Im PHPer [array] => Array ( [0] => And [1] => You? ) ) 2.array_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 ) 复制代码 代码如下: <?PHP $number = array("1","3","5","7","9"); $array = array("I","Am","A","PHP","er"); $newArray = array_combine($number,$array); print_r ($newArray); ?> 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 ) 3.range()函数——创建指定范围的数组： 不多说了，直接上实例—— 复制代码 代码如下: <?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); ?> range()函数的默认步进值是1！ 运行结果： 复制代码 代码如下: 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 ) 4.array_fill()函数——填充数组函数： 复制代码 代码如下: <?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>"; ?> 运行结果： 复制代码 代码如下: 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 ) 二、数组的遍历： 1.foreach遍历： foreach (array_expression as $value){} foreach (array_expression as $key => $value){} 闲话少说，上实例： 复制代码 代码如下: <?PHP $speed = array(50,120,180,240,380); foreach($speed as $keys=>$values){ echo $keys."=>".$values."<br />"; } ?> 运行结果： 复制代码 代码如下: 0=>50 1=>120 2=>180 3=>240 4=>380 2.while循环遍历： while循环遍历一般结合list函数，以下是实例 复制代码 代码如下: <?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>"; ?> 运行结果：
复制代码 代码如下: <?PHP $speed = range(0,220,20); for($i =0;$i<count($speed);$i++) { echo $speed[$i]." "; } ?> 运行结果： 复制代码 代码如下: 0 20 40 60 80 100 120 140 160 180 200 220 |
